After pre-season testing in Jerez, Mercedes were widely considered favourites for , appearing to have reacted well to changes to regulations mandating the use of turbo-hybrid engines. Mercedes' anticipated pace was realised at the season opener in Australia and Malaysia where Rosberg and Hamilton took dominant victories respectively, finishing far ahead of any other teams (although polesitter Hamilton retired in Australia due to engine failure). Their first intense battle for victory happened at the 2014 Bahrain Grand Prix as both drivers engaged in a close duel for the win. A late safety car seemingly swung the favour to second-place Rosberg, who had the benefit of being on a faster tyre, but after the restart Hamilton held firm in a close wheel-to-wheel encounter which passed without the pair making contact. In parc ferme after the race the pair engaged in a mock fight. It later emerged that Rosberg had used engine modes banned by Mercedes to give himself a power advantage over Hamilton in the closing laps. Tensions further arose when Hamilton discovered Mercedes had compiled a dossier for Rosberg to study on Hamilton's performance data. Hamilton, who had outqualified Rosberg in the first two rounds and crossed the finish line 17 seconds ahead of Rosberg in Malaysia, said "Someone in the team did a huge study on my pace in Malaysia. And since I arrived in Bahrain, Nico had a big document of all the places I was quick and used that to his advantage. So I will do the same for the next round in China and hope I can capitalise”.