Why did Ferrari struggle in Spain?

Advantage Mercedes as Ferrari falters (1:33)

Jonathan Legard looks back on a disastrous race for Ferrari, while rival Mercedes seals a 1-2 in Spain. (1:33)

BARCELONA, Spain -- Racing drivers are famous for seeking out excuses for poor performances. Often they are legitimate, sometimes they are interpretations of the truth and occasionally they have no grounding whatsoever. But speaking in the aftermath of the Spanish Grand Prix, Sebastian Vettel was brutally honest about why he wasn't on the podium on Sunday afternoon.

"We didn't have winning pace today, that's why we didn't win," he said. "There are a couple of things [that contributed]. In the short term, we all had our updates for this race but maybe the others have brought more than us and, on top of that, we had different tyres, which maybe suited others more than us.

"But what does it help? Why find excuses? The bottom line is we're not quick enough to win. That's what we have to address. Not 'did we have a disadvantage here', 'was that the case', 'was this the case', 'did the safety car help or not?' In the end we weren't quick enough and our tyres didn't last as long as others."

It sounds simple when you say it like that. On a given track, with a given tyre selection, Mercedes had the quicker car and Ferrari was second (maybe third) best. But there's always a story behind the result and this weekend it centred on tyres.

Did Pirelli's tyres offer Mercedes an advantage?

This particular story has its origins in January when the track surface of the Circuit de Catalunya was re-laid with a new, smoother tarmac ahead of pre-season testing. The objective was to eliminate a series of bumps in the braking zones that had drawn criticism from MotoGP riders. The MotoGP race at Barcelona is more lucrative for the circuit than F1 and in order to ensure the race stayed on the calendar, the surface, which was last renewed in 2007, was laid afresh.

Unlike the relatively abrasive surface that was there before, the new surface was super smooth. F1 teams and drivers first experienced it during a bitterly cold pre-season test, and a number of teams -- most notably Mercedes -- struggled with excessive overheating of their tyres.

The main problem was that the smoother surface was not resulting in as much physical wear from the tyres as before. The more rubber remaining on the tyre, the more heat it retains -- and on the softer compounds the surface of the tyre was getting so hot it started to blister. In agreement with the FIA, a decision was made to reduce the thickness of the tyres for the Spanish, French and British Grands Prix, in an attempt to avoid blistering on the newly-laid surfaces at all three circuits.

After being accused of favouring Red Bull in 2013 when it changed the construction of its tyres following that year's Spanish Grand Prix, Pirelli has been wary of altering its product midway through the season. But this weekend's change is tiny in comparison -- just 0.4mm of the tread was skimmed from the normal tyre -- and is common practice elsewhere in motor racing. What's more, by all accounts the thinner-gauge tyres were a success with no blistering reported during the race weekend. But in a sport measured in thousandths of a second, the smallest changes can make a noticeable difference.

Ferrari was one of the teams that didn't struggle as much with overheating in testing and, for the past two years, has had an advantage over Mercedes on Pirelli's softest compounds. The Mercedes has a tendency to overheat its rears and end up with tyre temperatures on the front and rear axles that don't match up. The Ferrari is much more balanced in this respect and therefore the drivers have found it easier to get their tyres in the sweetspot.

This weekend's compound choice of super-soft, soft and medium was actually quite aggressive for Pirelli, and was essentially two steps softer than last year given the fact all Pirelli's compounds have gone one step softer over the winter. But by reducing the tread by a tiny amount, Vettel said the softer compounds were acting more like the harder tyres that tend to suit Mercedes over Ferrari.

"Obviously we have heard many times that they are the same compounds and not harder, but then I don't think you need to be a genius to work out that if you skim the tyre it ends up being harder," he said. "It's one or the other, we may as well just have run harder tyres.

"Maybe it didn't suit our car as well as the other cars, but again what does it matter? We have to make it suit our car better than other cars, that's the way we want to turn it."

Did Ferrari mess up its strategy?

Even if the tyre tweaks did help Mercedes, Ferrari still appeared to throw away a solid podium finish when Vettel pitted for a second time from second position in the second half of the race. A good start had moved Vettel from third on the grid to second by Turn 1, although it soon became clear that the Ferrari was the slower car in the opening stint. Knowing this, Ferrari decided to be aggressive with its strategy in order to keep Vettel ahead of Valtteri Bottas and called its man in on lap 17 to prevent Bottas from benefiting from clear air on the undercut.

A slow stop meant Vettel emerged from his first stop behind the Haas of Kevin Magnussen -- an unfortunate turn of events that appeared to hand the advantage to Mercedes. But Bottas also had a slow stop two laps later and emerged behind both Magnussen and Vettel, keeping the Ferrari in a net second position once all the others in the top six made their first stop. But the pace of Lewis Hamilton and the Red Bulls during their opening stint meant a one-stop strategy started to become an option. Mercedes gave Hamilton the option of either strategy by pitting him on lap 26 while the Red Bulls went even longer into the race in the hope of having fresher tyres at the end of the race.

But by pitting Vettel so early there was no flexibility in Ferrari's strategy and the wear on the front left tyre (the one hit hardest around the Circuit de Catalunya) necessitated a second pit stop before the end of the race. A good opportunity to minimise the damage presented itself under a Virtual Safety Car and Ferrari took it, losing two positions to Bottas and Verstappen in the process.

Had Ferrari kept Vettel out, he would have started to lose all temperature in his front tyres as the rubber became thinner and thinner and, in a worst-case scenario, risked a failure. By comparison, Bottas -- whose tyres were two laps younger on a car that looks after its fronts better -- arrived in parc ferme at the end of the race with the canvas showing through on his front left. So by being aggressive in trying to fend off Bottas in the opening stint, Ferrari left itself vulnerable when a one-stop came into play later in the race. Misreading the tyres' wear life and assuming all drivers would two-stop was obviously a mistake, but given the new track surface, a rainstorm that hit on Saturday night washing the track clean and the unknowns that came with the thinner gauge rubber, it was also understandable.

Mercedes had the quicker car in Barcelona

The biggest single issue facing Ferrari in Barcelona was not having the fastest car. After being the team to beat at the previous three races, the Ferrari was not a match for the Mercedes on one-lap pace or race pace in Barcelona. But given Mercedes' pace in pre-season testing at the same track, perhaps that shouldn't come as a surprise. Had the first race of the season come at the Circuit de Catalunya immediately after testing, Sunday's result would have been in line with expectations and we would probably be applauding Ferrari for qualifying within two tenths of what looked like another dominant Mercedes.

"I think the circuit suits us, the tarmac suits us, the cold weather suits us and insofar I would be careful with predictions," Mercedes team boss Toto Wolff said on Sunday night. "We've seen performance levels swing from race track to race track and even from day to day, and this is how we tackle it at the moment, to try and perform every single day."

The Monaco Grand Prix in less than two weeks is a very different track and was the scene of Hamilton's worst performance of 2017. Once again, Mercedes are concerned their car may struggle to perform on the streets of the principality and there's every reason to believe the pendulum of performance will swing back towards Ferrari.

"I'm bloody worried," Wolff said when asked about Monaco. "We've seen in the last years that there was always tracks that suited us well and some that we weren't perfect on for whatever reason. It's very difficult to undo the DNA of a car and Monaco, Budapest, Singapore were all tracks where we underperformed a lot last year. It's a great challenge for us to come back this year, tame the diva."

Hamilton may have secured back-to-back wins and extended his lead in the championship to 17 points at the last two races, but the title race looks as compelling as it's ever been.