Despite all the talk of updates, as usual the ultimate performance seems to come down to who can get the tricky Pirelli tyres to work best for them.
The team confirmed their job sheet included data collection in order to correlate performance between the wind tunnel and track after recent auto improvements, set-up work, plus focus on engine development.
The tyres created all sorts of headaches for the teams.
It was the first one-two of the season for Mercedes, which had struggled to keep pace with the Ferraris. Running third, Sebastian Vettel would be the first to make the switch when he pitted on lap 18. "Honestly before the race we expected one stop was not going to be possible - at least to do the race quickly with one stop". But on Sunday, Lewis Hamilton was in devastating form. Ferrari called Vettel into the pits for on lap 18 causing Mercedes to bring in Bottas on the next lap. However, Hamilton's pace in that opening stint was absolutely mighty.
And with Mercedes money men in Barcelona to witness his dominant display, Hamilton dropped the biggest hint yet that he is ready to commit his future to the German team.
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Chelsea , Bayern Munich and Juventus have all emerged as suitors to sign a player who cost United £36million three years ago. Carrick's move to the dugout means he is the latest former United player to move into coaching.
In the end, the Ferrari's gamble would not pay off for Sebastian Vettel and likely cost him a podium finish.
World Championship rivals Hamilton and Vettel will both take part in in-season testing in Spain this week.
The Mercedes team principal revealed that all the details are nearly sorted, but they had to put talks on a back burner to focus on turning their season around after seeing Ferrari and Red Bull Racing be stronger than them in the first four races of the season. I'm very interested to see what happens in Monaco next time out as they should be in better shape in qualifying. The Team Redbull with Max Verstappen and Daniel Ricciardo lined up fifth and sixth. Giovinazzi was in the Sauber on day one but swapped to the Ferrari on Wednesday and used the hypersoft tire that will debut at the next race in Monaco to go second, 0.068s adrift of Bottas. "There is not a single person in the upper hierarchy of the team who has doubts, as far as I can tell". In a way, while it was a shame for Nico Hulkenberg and Pierre Gasly, it was lucky that there weren't more cars wiped out in that or drivers injured.
But now Sky Italia reports that Pirelli may test the pre-Spanish grand prix tyres in the post race test this week to see how they compare to the new ones. Lewis and Seb have been brilliant there in the past.
But after storming to victory in Sunday's Spanish Grand Prix, Hamilton insisted his passion for the sport is as strong as ever. His 1:18.441 was more than three seconds faster than the previous record - a 1:21.670 - set by Kimi Raikkonen in 2008.