Each MLB Team's Most Untouchable Prospect at Trade Deadline

As teams across Major League Baseball look to make moves ahead of the July 31 non-waiver trade deadline, there is no prospect in the game who is truly off limits.

But some are more off limits than others.

On that note, let's go through and pinpoint the most untouchable prospect on every MLB team. This is based on talent, MLB readiness and whatever immediate or long-term needs the club might have.

Going in alphabetical order by city, let's get to it.

The Arizona Diamondbacks didn't have a deep farm system to begin with, as B/R's Joel Reuter ranked it at No. 26 coming out of the draft.

It's three prospects shorter following the J.D. Martinez trade, with possibly more trades to come as the Diamondbacks seek their first postseason since 2011. Nobody is safe.

But if there's a prospect who should be safer than the others, it's Domingo Leyba.

The 21-year-old isn't a blue-chip talent and ranks as only the organization's No. 5 prospect at Baseball America. But having made it as far as Double-A, Leyba at least has solid MLB readiness going for him. He's also working on a career-high .796 OPS.

Right-hander Jon Duplantier deserves a shout-out for the excellent season he's having. But if that's turning him into a valuable trade chip, the D-backs should take advantage.

The Atlanta Braves won't be in buying mode at the deadline, so it's more than likely all of their top prospects are safe.

That's a long list by the way. With elite talent and plenty of depth, the Braves' farm system might be the best in baseball. For the "most untouchable" prospect within, you can take your pick.

The pick here is Ronald Acuna.

The outfielder is on a journey that's taken him from High-A to Double-A and now to Triple-A. He has an .868 OPS and 14 home runs overall. And the best part: He's only 19.

For Baseball America, Acuna has leaped from the No. 62 prospect in the game to the No. 10 prospect. Any guy who can do that in half a season might as well be kept in a vault.

Because the American League wild-card race isn't running away from them, the Baltimore Orioles could defy their losing record and buy at the trade deadline.

But with only MLB's No. 23 farm system coming out of the draft, the Orioles do need to exercise caution—particularly if teams come calling after Chance Sisco.

The 22-year-old catcher joined the Orioles organization in 2013, when he was a second-round draft pick. He's holding his own at Triple-A, putting him on the cusp of MLB.

Sisco lacks power and an exciting defensive profile, so he doesn't project as a superstar. But his .316 career average in the minors is evidence he can hit. Unless they can dig up another long-term answer at catcher, the Orioles should want to keep that ability to themselves.

Rafael Devers is the best prospect in the Boston Red Sox's depleted farm system and a long-term fit at a position where they badly need one.

To boot, he's coming into his own. Playing first at Double-A and now at Triple-A, the 20-year-old has a .964 OPS and 20 homers in 82 games. Hence he checks in as  No. 6 prospect.

With Travis Shaw and Pablo Sandoval out of the picture, third base is a major problem area for the Red Sox. Devers knows that as well as anyone.

"The fact that there is an opportunity there does inspire and motivate [me] to work harder," he said, per John Hand of WEEI.com.

The AL East-leading Red Sox will be in buying mode at the deadline. But Devers won't be going anywhere. 

The Chicago Cubs just traded their two best prospects to acquire Jose Quintana. Therefore, the word "untouchable" clearly doesn't apply to any of their remaining prospects.

In addition, their farm system isn't as loaded as it once was. And which of their remaining top prospects is the best is a matter for debate.

Adbert Alzolay, however, has the distinction of being both talented and rising fast.

In 17 starts at High-A and Double-A, the 22-year-old righty has posted a 2.95 ERA with 90 strikeouts and 25 walks in 91.2 innings. He's not a big guy, checking in at just 6'0" and 179 pounds. But he has good control and his stuff is getting more electric.

Meanwhile, the Cubs have all sorts of questions in their pitching staff. Just sayin'.

Through trade after trade after trade of various stars, the Chicago White Sox are building the farm system to end all farm systems.

They're not nearly ready to contend, though, so good luck prying any of their top prospects from their clutches. Especially if said prospect's name rhymes with "Moan Yoncada."

As a switch-hitter with power and speed who is just 22, Yoan Moncada is considered the best prospect in the league by, oh, pretty much everyone.

In case the White Sox needed an additional incentive to hold on to him, he's now in the big leagues. And he's there to work.

"We aren't bringing him here to sit," general manager Rick Hahn said, per MLB.com's Scott Merkin. "We are bringing him here to continue the development that needs to take place in Chicago."

Moncada is the best prospect in baseball, but the honor could pass to Hunter Greene before long.

Although he fell to the Cincinnati Reds at No. 2, many considered Greene the best prospect in the 2017 draft. He has the goods to excel as either a pitcher or a shortstop. The Reds should be excited.

For now, though, Nick Senzel should be a tad more untouchable.

Greene may be the golden boy, but Senzel tops Baseball America's rankings of Cincinnati's top prospects. Rightfully so. He was the Reds' No. 2 pick last year and has already hit his way to Double-A with an .877 OPS in 154 minor league games.

Senzel could debut at third base for the Reds next season. Once he has the position, he should keep it.

The Cleveland Indians should be running away with the AL Central race. But since they're not, they might feel the need to do something drastic at the trade deadline.

It shouldn't be something as drastic as trading Francisco Mejia.

Mejia, 21, wasn't the most well-known prospect in his first three pro seasons before leaping into the spotlight last season thanks to a 50-game hit streak. He finished with a .342 average and .896 OPS and is still rolling, with a .325 average and .907 OPS at Double-A.

Impressive stuff for a catcher, and Mejia also has more than enough arm strength for the position. If he's not obviously baseball's best catching prospect, there's a strong argument to be made for him.

In all, he's just the guy to upgrade a position that's been a weak spot for Cleveland since 2015.

The Colorado Rockies don't have an especially deep farm system, but there are two elite talents at the top: infielder Brendan Rodgers and right-hander Riley Pint.

If they're going to buy to keep their postseason hopes alive, Pint is the guy they should place out of reach.

He went No. 4 in the draft just last season. Although he was only 18 at the time, he was known to have a triple-digit fastball. And at 6'4" and 195 pounds, he boasts an ideal frame for pitching to boot.

Rodgers is a heck of a prospect and is far more advanced than Pint. He's already at Double-A, while Pint is honing his control and other abilities at Single-A.

What separates the two, however, is the fact the Rockies haven't had a homegrown ace since Ubaldo Jimenez. Pint is a prime candidate to be their guy.

If the Martinez trade is any indication, the Detroit Tigers will be in the business of swapping stars for prospects at the deadline. The prospects they already have aren't going anywhere.

That should go double for Matt Manning.

The Tigers drafted the right-hander out of high school last year and have every reason to be excited about him. He has a power fastball, a power curveball and room to add strength to his 6'6" frame.

Manning is also looking good at Low-A this season. In six starts, he has a 1.69 ERA and has struck out 24 batters in 21.1 innings.

There's an argument Manning is Detroit's second-best prospect after 2017 draftee Alex Faedo. But because of a recent change in MLB rules, Faedo is untouchable until after the World Series by default.

The Houston Astros are a World Series-caliber team that could be made all but unstoppable with the right moves at the deadline. None of their prospects should be untouchable.

If there is one they should be reluctant to part with, however, it's Kyle Tucker.

Tucker was arguably the Astros' best prospect coming into the year and has worked to remove all doubt throughout the season. The 20-year-old started at High-A and advanced to Double-A on the strength of a .922 overall OPS. He's clubbed 17 homers and stolen 19 bases.

Just two years after the Astros drafted him at No. 5 overall, Tucker is on track to join a growing list of young stars in Houston. They should only shift course if it means getting something special in a trade.

The Kansas City Royals are sitting on a decimated farm system. But while that's normally a cue to rebuild, the AL Central lead is close enough to spur them into buying. All their prospects should be on the table.

But if possible, they should hold on to Josh Staumont.

The 23-year-old is struggling to harness his control, two years after going in the second round of the 2015 draft. He's walked 70 batters in 83.2 innings at Double-A and Triple-A.

But with a fastball that sits in the mid-to-high 90s and can reach triple digits, Staumont's arm remains electric. He also has a dandy curveball. If nothing else, that's a relief ace profile.

Staumont figures to draw a crowd if the Royals do buy at the deadline. But they shouldn't move him unless the price is right.

The Los Angeles Angels are another team with a lousy farm system and a flimsy-yet-real shot at October.

With the AL West race long since having left them behind, the difference is they're only looking at a wild-card spot. If they're going to buy, they must be careful.

In particular, they should be in no hurry to give up Jahmai Jones.

The Angels chose Jones out of high school in the second round of the 2015 draft. He comes from a football background, yet he's adapted well to being a full-time baseball player, hitting a solid .276 with a .757 OPS in the minors. And he's still only 19.

Whether Jones is even a top-100 prospect is debatable. But he's the best prospect the Angels have and should be appropriately hard to obtain because of that.

Like the Astros, the Los Angeles Dodgers are a World Series-caliber team that shouldn't be afraid to pull off trades that could make the effort easier.

Still, they should be protective of Walker Buehler.

The Vanderbilt product underwent Tommy John surgery shortly after the Dodgers drafted him at No. 24 in 2015, and he returned to make only three appearances in 2016.

He's taking off like a rocket this year, though. In 16 starts at High-A and Double-A, Buehler has a 2.89 ERA with 91 strikeouts and only 20 walks in 65.1 innings. The 22-year-old has shot all the way to No. 17 in Baseball America's rankings.

With other top prospects to barter with, the Dodgers should put Buehler in the file marked "Hard to Get."

The Miami Marlins have a barren farm system, and their two best pitching prospects (Braxton Garrett and Tyler Kolek) are both recovering from Tommy John surgery. "Suboptimal" is the word.

On the bright side, there's more spotlight for Brian Anderson.

Anderson wasn't a name to know in 2015 or 2016, but he started to change that with a strong showing in the Arizona Fall League and is continuing to emerge in 2017. He has an .801 OPS in 92 games at Double-A and Triple-A. He also starred in the Futures Game at Marlins Park, going 2-for-4 with a double.

Already 24, Anderson is a candidate to reach the majors sooner rather than later. With the Marlins going into sell mode, it would take something truly baffling for him to leave the organization.

The NL Central-leading Milwaukee Brewers are going to be buyers at the deadline, but how far will they be willing to go?

If they're wise, not as far as dealing Lewis Brinson.

The 23-year-old has had ups and downs since going to the Texas Rangers in the first round of the 2012 draft. But he's retained a special blend of power and speed throughout and is on an upswing, with a .988 OPS, 10 homers and 11 steals at Triple-A.

Brinson is the best prospect in Milwaukee's farm system, which is saying something given it is one of the five best systems in the league. That should be good news for him in several ways, as it should allow the Brewers to swing a blockbuster or two without surrendering him.

The Minnesota Twins have hung in the race largely thanks to contributions from homegrown studs like Miguel Sano, Jose Berrios, Max Kepler and Byron Buxton.

They should make sure Nick Gordon is the next to join the list.

The son of former closer Tom Gordon and the half-brother of Marlins second baseman Dee Gordon, the 21-year-old's pro career got off to a sluggish start after the Twins drafted him at No. 5 in 2014. He's turning things around. Following a strong showing in the Arizona Fall League, he has an .819 OPS and seven homers at Double-A.

Questions remain about Gordon's defense and general upside, but he's nonetheless shot from No. 47 to No. 19 in Baseball America's top 100 this year. Assuming they don't trade him first, he could be manning shortstop for the Twins as soon as next season.

The New York Mets are far out of both the NL East and National League wild-card races, so they'll be looking to sell at the deadline. Their best prospects aren't going anywhere.

Above all, that includes Amed Rosario.

The slick-fielding, slick-hitting shortstop entered the season as a top-10 talent and has done nothing to hurt his stock. He's played in 87 games at Triple-A and has hit .330 with an .841 OPS.

Maybe the only question is why Rosario isn't in the majors yet. Bob Klapisch of NorthJersey.com suggested it could be because the Mets want to shield him from a disgruntled Asdrubal Cabrera. That seems unlikely, but stranger things have happened in Metsland.

Regardless, Rosario is a key part of the Mets' future. They should keep it that way.

The New York Yankees began rebuilding last year, but all bets are off with their farm system. By trading Blake Rutherford to the White Sox, they indicated they're willing to pay the price for upgrades.

But count on this much: Gleyber Torres will still be around come August 1.

He's hard to move at the moment, for one. He had Tommy John surgery in June, which will keep him out of action until next year.

Second, he remains the Yankees' most exciting prospect. As a 20-year-old who can handle shortstop and was raking with an .863 OPS at Double-A and Triple-A before his injury setback, it's no wonder he still checks in at No. 3 overall with Baseball America.

The Yankees have plenty of other prospects to deal for additional upgrades. They should do so and leave Torres alone.

With a Sonny Gray trade feeling more imminent by the day, the Oakland Athletics' farm system should soon get a bunch of shiny new toys.

But for now, Franklin Barreto is the best they have.

It may not look like it in light of the .190 average and .642 OPS he put up in 11 games with the big club before going back down to Triple-A. There's also a question of where he fits best defensively in the long run.

But one thing about the long run that seems certain is Barreto will hit. The 21-year-old has a .798 career OPS in the minors and has showcased a feel for hard contact that will play well regardless of where he ends up on defense.

The Philadelphia Phillies won't be buying at the deadline. And thanks to a shortage of trade chips, they may not add much to their farm system, either.

Regarding the players who already are on the farm, outfielder Mickey Moniak and right-hander Sixto Sanchez are certainly untouchable. But the pick here is Scott Kingery, whose indispensability is increasing.

The 23-year-old has a .943 OPS at Double-A and Triple-A. And after hitting only eight homers in his first two pro seasons, he's already up to 22 this year.

"I think my power has always been there," he said in June, per Kelsie Heneghan of MiLB.com. "[I've just] changed a few things in my swing that has allowed me to unlock some of that power."

Kingery wasn't in Baseball America's top 100 at the start of the year. Now he can be found at No. 52. That's quite a leap.

Although the Pittsburgh Pirates suddenly can't seem to lose, there's still a good bit of distance between them and the second NL wild card. They won't be big buyers, so their top prospects can rest easy.

Arguably belonging at the top of the list is outfielder Austin Meadows. But as he's lost steam this season, Mitch Keller has only gained steam.

The 21-year-old righty has had trouble staying healthy since going to the Pirates in the second round of the 2014 draft. But he's been mostly effective when he's pitched and has a solid 3.47 ERA with 57 strikeouts and 19 walks in 62.1 innings at Low-A and High-A.

With a strong fastball/curveball combo and good command, Keller has the goods to rise fast. That should work out for the Pirates, who may soon need a replacement for Gerrit Cole.

The San Diego Padres are yet another bad team with a farm system full of prospects who don't have to worry about moving.

The best going into the season was right-hander Anderson Espinoza. But while his stock has been ruined by bad health, good health is elevating Cal Quantrill's stock.

The 22-year-old Stanford product might have been the No. 1 pick in the 2016 draft. Alas, he suffered an elbow injury that required Tommy John surgery and bumped him to the Padres at No. 8.

But Quantrill, whose father, Paul, pitched in 14 major league seasons, is back and making a strong impression with a 3.87 ERA in 15 starts at High-A and Double-A. His plus fastball and plus changeup are in good shape.

Quantrill has already climbed to No. 21 in Baseball America's rankings. Before long, he should climb to the big leagues.

The San Francisco Giants don't have a deep farm system and, because of a shortage of trade chips, may not add much to it.

Among the prospects it already contains, meanwhile, it's hard to pick out one who is untouchable because there arguably isn't a blue chip to be found. There is, however, a rarity by Giants standards in Chris Shaw.

Shaw, the No. 31 pick in the 2015 draft, is a slugger in an organization that has had a hard time producing sluggers. He has a powerful build, at 6'4" and 235 pounds, and he owns a .506 slugging percentage and 48 homers in three seasons.

The 23-year-old looked expendable when he was playing strictly at first base. But now he's seeing action in left field, he's no longer blocked by Brandon Belt and is a possible solution to a big problem.

The Seattle Mariners traded for David Phelps on Thursday, as Greg Johns of the league's website reported, and they may have more trades left in them. Their top prospects should be on their toes.

That includes outfielder Kyle Lewis, but injuries have kept his stock from rising. He's the anti-Nick Neidert, who is looking more and more like a keeper.

A second-round draft pick in 2015, Neidert quietly dominated the last two seasons and is pushing his game to another level. In 19 starts at High-A, he has a 2.76 ERA with 109 strikeouts and only 17 walks in 104.1 innings.

Good stuff for a 20-year-old who was drafted out of high school. It speaks to how crafty he is with an arsenal of just-OK pitches.

Neidert is a candidate to move quickly to the big leagues, where he could help a starting rotation that needs a ray of hope.

The St. Louis Cardinals have had a rough season, but president of baseball operations John Mozeliak told reporters that the team has to be "open-minded."

That could mean buying at the deadline, which might put their best healthy prospect on the table. That's catcher Carson Kelly, who became expendable when the Cardinals extended Yadier Molina through 2020.

But don't expect St. Louis' best unhealthy prospect to go anywhere.

That's Alex Reyes. Even as he recovers from Tommy John surgery, he rates as Baseball America's No. 1 pitching prospect. It should be no secret why after what he did in 2016. He came up and showed his electric stuff is more than good enough for The Show.

He'll be back in 2018. And he should still be in a Cardinals uniform.

Don't sleep on the Tampa Bay Rays. If they make the right moves at the deadline, they could swipe the AL East title from under Boston's nose.

How will anyone know if they made the right moves? If none involve Willy Adames.

Acquired in the trade that sent David Price to Detroit in 2014, Adames has since evolved into one of baseball's best prospects. He checks in at No. 13 overall for Baseball America and gets good remarks for his bat, glove and makeup.

"Willy has it," Tampa Bay farm director Mitch Lukevics said in January, per Bill Chastain of MLB.com. "He has the skills that make him a good player, and he has good intangibles to go along with skill. At a young age, he's accomplished quite a bit."

Right-hander Brent Honeywell is also a heck of a prospect. But Adames is a player the Rays could build around.

The Texas Rangers are still technically in the race, but they seem more likely to sell at the deadline than to chase something that's not really there.

If they do decide to go for it, the last thing they should do is subtract Leody Taveras from an already weak farm system.

Taveras doesn't have impressive numbers in two minor league seasons, as he owns just a .681 OPS in 164 games. But don't let that fool you. He's described by MLB.com as a "legitimate five-tool center fielder." And at just 18, there's no hurry for him to figure it out.

He fits well in Texas' future. When he's ready, Taveras should slot nicely alongside Nomar Mazara, Rougned Odor and Joey Gallo.

The Toronto Blue Jays likely aren't buying, and they're certainly not trading Vladimir Guerrero Jr. if they do.

Guerrero has risen to become Baseball America's No. 2 prospect, and it's easy to see why. He's only 18 yet has an .877 OPS in 78 games at Single-A and High-A.

When it comes to hitting, he's not a chip off the old block.

"We're different," he said of comparisons to his father, a former MVP who spent 16 seasons in the majors, to Jorge L. Ortiz of USA Today. "He swung at everything, but I don’t. I look for my pitch and try to make good contact. He likes it, because he has his way and I have mine."

As young as Guerrero is, he could rise fast and be ready for the big leagues by 2019. Provided he isn't traded beforehand, that would be just in time for him to take over for Josh Donaldson at third base.

The Washington Nationals should still be seeking a bullpen worthy of October but must also be mindful of a future that could involve losing Bryce Harper after 2018.

That's a big reason to keep Victor Robles around.

After signing for a modest $225,000 in 2013, Robles turned some heads in 2014 and even more in 2015. So it goes in the here and now, where he is a widely considered one of baseball's elite prospects.

Between his power, speed and arm strength, he has tools galore. He also has numbers, as he's rocking an .881 OPS in 74 games at High-A.

"He just does stuff each night," Tripp Kiester, manager of the Potomac Nationals, told Chelsea Janes of the Washington Post. "It's pretty special. He does some things, and you just think, 'Huh.'"

Another thing: Robles is only 20. So if the Nats do lose Harper, they would be ready to replace him with another ultra-young, ultra-talented player.

Stats courtesy of Baseball Reference and MiLB.com and are current through Wednesday, July 19.