Which PGA Tour Players Will Have a Regression in 2015?

On the PGA Tour, only a select few players have been able to play consistently good golf across the majority of their careers. 

Look at the top five players in the Official World Golf Ranking right now: Rory McIlroy, Adam Scott, Jim Furyk, Sergio Garcia, Henrik Stenson. All have had wild turns in fortune during their time on tour.

Indeed, all players' performances vary from year to year. A significant regression then, isn't a two-spot drop in the Official World Golf Ranking or recording two wins rather than three. For our purposes, "regression" will include a significant slide in the Official World Golf Ranking, a drop in final FedEx Cup points standing or position on the money list. Fewer top-10 and top-25 finishes, as well as wins, are also hallmarks of serious decline. 

In this list, our regressors will take two forms: players who have overperformed recently due to come back to earth, and formerly top-tier players who are due to continue playing at a decidedly non-top level. 

With that said, on to the guys whose 2014-2015 seasons won't receive much attention in the annals of PGA Tour history. 

Relative to his previous seasons on tour, Jimmy Walker's 2013-2014 campaign was an incredible overperformance. 

And while it's accurate to label the Oklahoma native's 2013-2014 as a breakout season, it could be more precisely called a "very hot streak followed by pretty good play."

Walker won three times last season, yes. But those wins came in a very brief period of time. 

While Jimmy Walker has taken a step forward, to be sure, if he duplicates his performance from the second half of the the 2013-2014 season across the whole of 2014-2015, he'll be looking at a winless season. And when a golfer goes from three wins to zero, that's a significant regression. 

Consistency has defined Jim Furyk's career on the PGA Tour. And while he didn't raise a trophy in 2014, Furyk did notch four second-place finishes. He made the cut in all 21 of his PGA Tour starts and totaled 11 top-10 finishes and recorded his most cuts made and top-10s since 2009.

Furyk, however, turns 45 this season. His putting declined slightly last year while his greens in regulation percentage remained in the 67 to 68 percent range, which it has for most of his career.

Averaging just 279.3 yards per drive last year, he can't afford the loss of distance aging brings, and he's right up against the point in a player's career where length off the tee begins to decline. 

Furyk's slight overperformance in 2014 paired with the inevitable results of aging should yield a regression in 2015. 

Another aging golfer, Steve Stricker, saw his "part-time professional golfer" approach work well in 2013. Not so much in 2014.

Expect the "not so much" trend to continue this season.

In 2013, the Wisconsin native tallied eight top-10 finishes in 13 starts, including four second-place finishes. Last year, Stricker managed just two top-10s in 11 starts. 

Stricker turns 48 in February. His age and his limited playing schedule make it impossible to believe he'll be able to repeat his 2013 performance. Expect a drop-off from his 2013-2014 numbers, too, as one of the greatest putters in recent memory has begun his ride into the sunset. 

Largely an embarrassment at the Ryder Cup (where he went 0-1-1), Webb Simpson wasn't exactly having a brilliant close to the 2013-2014 season before he hopped the plane to Gleneagles. He was unimpressive at the BMW Championship (T53) and the Tour Championship (T23). 

If he experiments with a shorter putter this season ahead of the anchored putter ban that's coming down the pike in 2016, as he's suggested he'll do, expect a drop-off from his 2014 form. 

Simpson was 16th in strokes gained: putting in 2013 and 34th in the category in 2014. Thus, he relies heavily on the flatstick. If he falters on the greens with a traditional-length putter, it's difficult to imagine him notching back-to-back winning seasons. 

It's becoming difficult to imagine Luke Donald was once the No. 1 golfer in the world. Perhaps the ultimate sign of how far he has fallen was European Ryder Cup captain Paul McGinley electing not to use one of his captain's picks to add Donald to the squad this year.

The tour's leading earner in 2011, Donald has gotten steadily worse since; he made just 13 of 17 cuts in 2014. Further, the Englishman only managed three top-10 finishes: his lowest number since 2008. 

Since 2012, his number of top-10 finishes has fallen from eight, to five, to the aforementioned three. Thus, Donald's decline is visible in that figure alone. Additionally, he hasn't won since 2012 and finished 89th in the final FedEx Cup standings.

Whatever indicator of success you choose to look at, Luke Donald is regressing to his early-2000s form. 

Over the course of 2014, Kevin Na rose from No. 233 in the Official World Golf Ranking to No. 34. 

Na made 20 of 27 cuts in 2014. He finished inside the top 10 six times, including two second-place finishes (most notably losing to Hideki Matsuyama in a playoff at the Memorial). Na's 14 top-25 finishes improved on his 2013 number by 13. In terms of prize money and FedEx Cup points, the 2013-2014 season was Na's best ever. 

Na's 2014-2015 season is off to a weird start. He withdrew from the Shriners Hospitals for Children Open with an illness, then flew overseas shortly thereafter for the Korean Open. He was disqualified from that event following the second round when he signed an incorrect scorecard. 

The eternally slow-playing Mr. Na will also be under the microscope all season as the poster child for maintaining a snail-like pace on the course. Given Na's flappability, this isn't likely to aid his performance. 

The early-season weirdness is a bad omen in a year in which Na was always going to be closely watched. The South Korean is due for a regression this season. 

Phil Mickelson may be optimistic about his future as a professional golfer, but that optimism seems misplaced. 

Mickelson is 44. He's been on tour for more than 20 years and has lingering health issues, including psoriatic arthritis. 

2014 marked only his second winless campaign since 2000. He had his fewest number of top 10s since 1992. If we look at his impressive showing at the PGA Championship as an outlier, rather than an indication that he still has it, the picture becomes even bleaker. Mickelson didn't even make it to the Tour Championship. 

His 2013 season, in which he won twice, has taken on the appearance of something of a last hurrah for the left-hander in the wake of a dismal 2014. 

Certainly his drop from fifth (.656) in 2013 to 50th (.249) in strokes gained: putting is a troubling sign of aging.

While Mickelson may perform slightly better this year than he did in 2014, the descent has clearly begun. 

All stats via PGATOUR.com

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