5 Drivers with the Most to Prove Ahead of 2015 Spanish Grand Prix

Nico Rosberg is a man under pressure.

Team-mate Lewis Hamilton's victory in Bahrain gave him a 27-point lead in the drivers' championship. Winless Rosberg, yet to qualify or finish ahead of Hamilton, is just one point clear of third-placed Sebastian Vettel.

If he wants to take the title fight to Hamilton again, the German needs to put in a stellar performance at the Spanish Grand Prix—and he isn't alone.

Joining Rosberg, here are four other drivers who stand out as needing to produce something special in Catalunya.

Nico Rosberg's tough, battling drive in Bahrain went some way to rekindling hopes we could have a proper title fight in 2015.

But as well as the German drove, the unfortunate truth is that Lewis Hamilton drove even better. Even without the brake failure that cost Rosberg second on the penultimate lap, he would not have beaten his team-mate.

So Rosberg heads to Spain with the unenviable distinction of being the only driver to have finished all of 2015's eight competitive sessions (four qualifyings, four races) behind his team-mate.

He has also spent fewer laps—just 10—ahead of his team-mate than any other driver.

The points gap to Hamilton stands at 27 points, and Rosberg can't afford for it to grow further. He absolutely needs to finish ahead in Catalunya—preferably by being quicker in both qualifying and the race.

While the front-runners are attracting most of the headlines and attention, there's something curious going on at the rear of the field. Roberto Merhi is being comprehensively out-driven by Will Stevens.

A glance at their junior careers suggests this shouldn't be happening. Though neither possesses a glittering record, Merhi's is significantly better than his team-mate's.

Lower-formulae form doesn't always transfer to F1, but it does tend to give a broadly accurate picture—so Merhi being this far behind Stevens is very strange indeed.

Part of the difference could be due to the weight of the two drivers. Pitpass lists Stevens' weight as 63 kilograms and Merhi's as 76 kilograms. If the modified MR03 is at or above the minimum weight (and therefore does not need ballast), that 13 kilogram difference translates to around 0.4 seconds of time lost per lap.

The Spaniard has also had an ill-fitting seat for at least part of the 2015 campaign, as reported by GrandPrix 247.

Whatever the cause of the difference between the two, Merhi is not guaranteed his seat for the whole season. He drives on a race-by-race basis, constantly looking over his shoulder, aware he could be replaced by a well-funded pay-driver at any time.

Catalunya is a circuit he knows well. If he's to have any hope of hanging on at Manor—or leaving with his reputation enhanced—Merhi needs to put Stevens in the shade.

Pastor Maldonado is a master of disguise, having spent the last four-and-a-half years brilliantly hiding the fact he's a talented racing driver. His special trick in 2015 is being one of only five drivers to start a race but fail to score a point.

In fairness, it hasn't always been his fault; he was taken out in Australia at the first corner, suffered a puncture at Turn 1 in Malaysia and was hit by Jenson Button in China.

But part of being a successful F1 driver is making your own luck: Qualifying well enough to minimise the risk of first-corner carnage, not spinning and losing time so you end up fighting a McLaren.

While team-mate Romain Grosjean (holder of a 4-0 qualifying lead) has tamed his wild side and become a respected and reliable racer, Maldonado has not. Grosjean will now take a points-worthy car and, more often than not, score points with it.

Maldonado will find a way to end up pointing the wrong way, asking the marshals for a push on his way to finishing 12th.

He showed how good he can be by winning the 2012 Spanish Grand Prix, but his 2015 record stands at three retirements and one 15th-place finish. Drivers are judged on results, and Maldonado is not getting them.

He doesn't need to repeat that stunning victory this year in Spain, but outqualifying Grosjean and producing a calm, quick drive to a point or two would do him the world of good.

Kimi Raikkonen finally got the better of Sebastian Vettel at the Bahrain Grand Prix. The Finn had significantly better race pace and, in all likelihood, would have finished ahead even without his team-mate's errors.

But doing it once isn't enough to remove the risk of being shunted into the role of No. 2 driver.

Despite tending to be just as quick as Vettel over a race distance, Raikkonen is 23 points behind his team-mate in the standings. His retirement in Australia accounts for a chunk of that gap, but the rest can be directly or indirectly linked to poor qualifying displays.

Fifth in Melbourne, 11th in Sepang, sixth in Shanghai and fourth in Sakhir. In just four races, Raikkonen has qualified a total of 17 places behind Vettel.

He has nothing to prove on the Sunday—we've seen ample proof already this year that Raikkonen is very good over a long run. But at a track like Catalunya, where overtaking is so difficult, a poor grid slot can make race pace irrelevant.

Raikkonen needs to prove to Ferrari that he is just as capable of taking the fight to Mercedes as Vettel is. That means beating the German in qualifying—starting in Spain.

Daniil Kvyat must have thought all his Christmases had come at once when he was promoted from Toro Rosso to Red Bull. At just 20 years of age, he was set to become the youngest driver at a front-running team since Ricardo Rodriguez at Ferrari in 1963.

But there was a sense that, after just one season of F1, he wasn't quite ready for it—and what we've seen so far in 2015 has done nothing to shake that belief.

In Kvyat's defence, his car hasn't helped. The Renault-powered RB11 has proved both uncompetitive and unreliable, breaking down before the start in Australia and grinding to a halt after just 15 laps of the Chinese Grand Prix.

He also had, per ESPN, brake and power unit issues in qualifying in Shanghai, while Autosport reports an energy issue compromised his Saturday in Bahrain.

But team-mate Daniel Ricciardo is doing much better despite his own problems. The Australian has been ever-present in Q3; Kvyat has only been there once.

In qualifying the Russian trails 4-0, and in terms of points, it's 19-4 in Ricciardo's favour.

Kvyat's poor start to the year is more down to the car than the driver, but he's still under pressure to perform.

With Max Verstappen looking like a star of the future, Kvyat needs a trouble-free weekend in Spain to show Red Bull he's more than just a one-season wonder.