Ferrari's Sebastian Vettel was easily fastest in first free practice for the Bahrain Grand Prix on Friday, in a generally quiet session that saw problems for his team mate Kimi Raikkonen.
Vettel was a full four tenths faster than Red Bull's Daniel Ricciardo, whose team mate Max Verstappen was a similar distance further back. Having topped the times early in the session, Mercedes put their feet up and opted not to show their qualifying pace.
After the dramas of seven days ago in Shanghai, practice this week was very much business as usual. Ricciardo was the first man to post a time in the 90-minute session, the first half of which was given over to long runs
The Mercedes drivers traded places back and forth at the top of the timings. Anything Valtteri Bottas was able to do was quickly bettered by his team mate, Lewis Hamilton.
After the midway point, attention turned to qualifying simulation. Force India's Sergio Perez enjoyed a brief moment out in front with a lap of 1:34.095s ahead of a brace of Williams drivers.
With 30 minutes remaining, it was Vettel who produced a step change in the laptimes. He posted what would prove to be the session's best effort of 1:32.697s, 1.4s faster than anyone up to that point. Even so, that was slightly slower than FP1 times in 2016, indicating there's a lot of improvement to come.
The Red Bull boys responded and were able to slip into the yawning gap between Vettel and Perez, but there was no attempt by Mercedes to try and set session-best times. Hamilton ended in tenth place, while Bottas was in 14th. However the team insisted that their programme was going according to plan and there were no issues causing concern.
In the second Ferrari, Raikkonen was unable to match Vettel's performance. He was forced to park in a run-off area on the backstraight with smoke coming out of the rear of the car. Also suffering technical issues was Stoffel Vandoorne, whose McLaren came to a halt at turn 10 with 20 minutes remaining the end of the session with an MGU-H problem. The team hopes to replace the engine in time for FP2.
There were no stoppages during the session, but Felipe Massa suffered a scary high-speed spin at turn 13 in the final ten minutes. Massa was able to limp back to pit lane despite reporting that he had completely lost the brakes on the Williams.
Free Practice 1 results