Ferrari driver Sebastian Vettel posted the quickest time during the opening day of pre-season testing at the Circuit de Barcelona-Catalunya.
Vettel set his lap of 1:24.939 on the Medium tyre 20 minutes before the lunch break, with his time remaining unbeaten throughout the afternoon session.
World Champion Lewis Hamilton was second, 0.470s behind Vettel, though was the most productive driver as he accumulated over two race distance worth of laps in his Mercedes W07 Hybrid.
Red Bull's Daniel Ricciardo recovered from a slow start to clock the third quickest time, ahead of Williams’ Valtteri Bottas.
Force India development driver Alfonso Celis Jr. put the first laps on the VJM09 and improved with a late run on Soft tyres to place fifth.
McLaren’s Jenson Button enjoyed an encouraging day in the MP4-31 as he achieved over a race distance worth of laps and finished sixth, having set a late time on Soft tyres.
Carlos Sainz Jr. was seventh for Toro Rosso as it debuted its Ferrari-powered STR11 in an interim all-blue test livery.
Sainz's day ended prematurely after Toro Rosso detected an irregularity with the gearbox data and ended running as a precaution.
Marcus Ericsson was the final river to take to the circuit during the morning session but racked up the laps in the afternoon to place eighth in Sauber’s 2015 car.
Reigning DTM Champion Pascal Wehrlein sampled the new Manor MRT05 for the first time and finished ninth after a steady start.
Haas made its Formula 1 debut an hour into running but it caused the biggest drama of a quiet day when Romain Grosjean’s front wing collapsed along the pit straight.
The session was briefly red flagged while Grosjean returned to the pits unharmed, before re-joining the action mid-afternoon.
Renault’s Jolyon Palmer briefly topped the times during a damp start to the day but slid down the order and finished at the foot of the standings.
|3||3||Daniel Ricciardo||Red Bull||1:26.044||86|
|5||34||Alfonso Celis Jr||Force India||1:26.298||58|
|7||55||Carlos Sainz Jr||Toro Rosso||1:27.180||55|