A rejuvenated Felipe Massa put Williams on top of pre-season testing on Tuesday morning at the Circuit de Barcelona-Catalunya.
A late run on supersofts in the final half hour of the session saw Massa become only the third driver to break the 80s mark in pre-season testing in Spain. His lap of 1:19.726s was almost two tenths faster than anyone else.
The first day of the second week of pre-season testing started off bright and sunny, but rather chilly. Mercedes' Lewis Hamilton was the first driver to set flying lap times when the track went green, but his initial efforts were soon bettered by Sebastian Vettel in the Ferrari.
An hour into the session, Daniel Ricciardo put in the best lap so far seen from the RB13 to top the times with 1:20.964s. He was able to chip away at that time throughout the rest of the session to stay ahead of his rivals, until the final half hour when Massa went fastest. Ricciardo did close the gap on Massa with his final run on ultrasofts to consolidate second place with 1:19.900s.
Hamilton stuck to an established programme of running stints consisting of 16-17 laps on soft compound tyres. With more fuel on board for the early laps he wasn't able to threaten Massa and Ricciardo. He ended third fastest for the morning, just ahead of another solid showing from Vettel who completed 81 laps.
Force India's Esteban Ocon and Haas' Kevin Magnussen enjoyed a private tussle over fifth place on the timesheets. Toro Rosso's Dannil Kvyat had a quiet time of it and had to be content with seventh fastest.
In an almost trouble-free morning on the track for everyone, McLaren's Stoffel Vandoorne initially clocked up 34 laps but was then conspicuously absent for the latter half of the session. McLaren racing director Eric Boullier later confirmed an engine issue, but said he hoped Vandoorne would be able to get back out during the afternoon session.
There were also sensor issues for Renault which saw Jolyon Palmer's car grind to a halt in the pit lane just 90 minutes and 15 laps into the session. The car had to be retrieved by team personnel and the decision was made to change the engine, meaning that Palmer had to sit out the rest of the morning.
Palmer's absence allowed Sauber's Pascal Wehrlein to finish ahead of the Renault in the times. He had slowly inched his way forward after a quiet start to the day. It was Wehrlein's first day of testing after missing out last week with a back injury sustained in January's Race of Champions.
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