The session was barely five minutes old when Magnussen leapt from his cockpit with flames licking from the R.S.16's airbox and fuel leaking from a vent. The fire was quickly dealt with, with mechanics working to drain the fuel tank, but race control had no choice but to bring out the red flags for nearly 15 minutes as the smouldering car was removed and the extinguishant cleared from the pit lane.
When the session resumed, Rosberg quickly went fastest with 1m 35.793s on Pirelli’s soft rubber. Hamilton managed 1m 35.798s, but as Rosberg later improved to 1m 35.227s, Hamilton could only trim his time to 1m 35.721s. The Briton had one big lock-up moment which sent him momentarily off track, while Rosberg later had snap oversteer at Turn 10 on the mediums, which sent him off the road at Turn 11. Despite that, the Silver Arrows were also faster on mediums that the Ferraris were on their softs.
As for the Prancing Horse, Kimi Raikkonen again headed Sebastian Vettel, with 1m 36.315s to 1m 36.331s; the German initially complaining of serious tyre balance problems.
Behind the red cars, Fernando Alonso was an encouraging fifth for McLaren as he trialled Honda’s upgraded power unit. The Spaniard was only 1.283s off the Mercedes pace, using the same soft rubber.
Red Bull’s Daniel Ricciardo and Max Verstappen only used the hard and medium tyres on their way to sixth and seventh. On the former the Australian lapped marginally faster in 1m 36.753s than he had on the latter. On the hards the Dutchman struggled with understeer on his way to 1m 36.973s.
The hard rubber also took Nico Hulkenberg and Sergio Perez to eighth and ninth places in their Force Indias, on 1m 37.513s and 1m 37.602s respectively. The other McLaren of Jenson Button didn’t run the new Honda ICE or the soft tyres but was 10th on 1m 37.613s.