BARCELONA, Spain -- Sebastian Vettel returned Ferrari back to the top of the timing screens as he went fastest in the opening day of this week's in-season test in Barcelona.
A soft tyre lap of 1:23.220 set in mid-afternoon was enough to see Vettel beat Mercedes driver and championship leader Nico Rosberg to top spot by 0.117s. Ferrari had been focusing on a solution to its qualifying struggles on Saturday, where it surprisingly failed to beat either Red Bull in qualifying. It had been slower than Red Bull through the technical final sector over the weekend -- which hampered Kimi Raikkonen's chances of victory during the grand prix -- but Vettel showed improvement in testing, recording the fastest time through that part of the track.
Like Vettel, Rosberg's quickest time was set on the soft tyre. Vettel's headline time was set at roughly the same time qualifying would have been run, during a full simulation, but it is worth noting Ferrari qualified 1.1s off the pace when it mattered last Saturday. That is a good example of why headline times can be misleading in testing, as it is unlikely Rosberg and Mercedes have lost that amount of time to the Italian team in three days. As it did on most days in winter testing, Mercedes led the lap chart with 117 next to Rosberg's name.
Behind Rosberg was Jenson Button, who led at the lunch break with a time of 1:23.753 on the super-soft tyres. That time remained his fastest for the rest of the afternoon on another encouraging day for McLaren-Honda. Romain Grosjean brought Haas up to fourth late in the day with a run on the ultra-soft tyres, which will get their official debut at the Monaco Grand Prix. His 1:23.882 put him six tenths down on the lead.
Pascal Wehrlein climbed to fifth in the final hour with a 1:24.297, one second off the pace but within half a second of Button's lap time on the same compound. Red Bull's Daniel Ricciardo ended the day in sixth position just 0.01s behind Wehrlein's time, completing 89 laps.
GP2 driver Pierre Gasly clocked 78 laps for Toro Rosso, ahead of Force India driver Alfonso Celis. The Mexican driver had been told he needed to up his pace by senior race driver Sergio Perez last week and moved within 2.2s of Vettel's headline time late in the day, albeit on the quicker super-soft tyres. The Mexican driver finished one lap shy of completing a century of laps.
Williams development driver Alex Lynn finished the day 2.8s off the lead, having spent much of the morning testing a car with radical front and rear wings the team said were collecting data relevant to 2016 and 2017. Esteban Ocon, the reigning GP3 champion, brought up the rear for Renault as it tested its new B-spec engine, 3.3s down on the pace and one of only three drivers to record a century of laps. As Renault was testing its upgrade it is unlikely the team was looking for raw performance at this stage, with a big step forward expected when the team introduces the upgrade to its race cars for the Canadian Grand Prix.
Times at close:
1. Sebastian Vettel - Ferrari - 1:23.220 - 103 laps
2. Nico Rosberg - Mercedes - 1:23.337 - 119 laps
3. Jenson Button - McLaren - 1:23.753 - 86 laps
4. Romain Grosjean - Haas - 1:23.882 - 96 laps
5. Pascal Wehrlein - Manor - 1:24.297 - 86 laps
6. Daniel Ricciardo - Red Bull - 1:24.307 - 89 laps
7. Pierre Gasly - Toro Rosso - 1:24.821 - 78 laps
8. Alfonso Celis - Force India - 1:25.467 - 99 laps
9. Alex Lynn - Williams - 1:26.071 - 86 laps
10. Esteban Ocon - Renault - 1:26.530 - 105 laps