Sebastian Vettel set the fastest time of the first morning of testing in Barcelona as a number of new cars broke cover.
Driving the new Ferrari SF16-H, Vettel set the pace with a 1:24.939 having traded fastest times for a spell with Lewis Hamilton. The reigning world champion was second fastest during the morning session, 0.470s slower than the Ferrari. Somewhat predictably Mercedes was able to boast the highest mileage of the morning as Hamilton completed 66 laps.
Valtteri Bottas was third fastest for Williams having been one of the first cars out on track, with the new FW38 ending the morning 1.1s adrift of Vettel's best time. Bottas ended the session 0.6s clear of Daniel Ricciardo in the RB12 which was unveiled on Monday morning, with a burst of laps from the Red Bull in the final hour propelling it up the timing screens.
Another new car to be seen for the first time on Monday was the Toro Rosso STR11, with Carlos Sainz taking the car out on track in a dark blue testing livery. The team made an encouraging start, with Sainz completed 35 laps and setting the fifth fastest time, 2.2s slower than Vettel.
McLaren's pre-season got off to a more encouraging start than a year ago, with Jenson Button putting 35 laps on the MP4-31 in the opening four hours. Button's best time was 2.7s off the pace, but left him sixth in the standings and more importantly displayed a solid start reliability-wise for Honda.
Marcus Ericsson was seventh for Sauber in last year's C34, completing 36 laps after failing to emerge in the first two hours of the day. Sauber will run its 2015 car throughout the first test before launching its new car next week.
For a first day of pre-season testing the majority of the teams made serene progress throughout the morning, with only one red flag occurring in the final hour before lunch. It was a somewhat concerning failure for the new Haas team as Romain Grosjean lost his front wing on the pit straight, with marshals needing ten minutes to clear away the debris.
The issue ended Grosjean's running for the morning early after just 13 laps, the second lowest total of the session with only Pascal Wehrlein completing less mileage in the Manor. The new Manor MRT05 was first seen two hours in to the session and after a slow start Wehrlein completed a timed lap in the final half hour, albeit 8.5 seconds off the pace.
Splitting the Haas and Manor on the timing screens were two more cars unveiled on Monday morning in the form of the Force India and Renault. Alfonso Celis put 21 laps on the VJM09 while Jolyon Palmer was only able to manage 15 laps in the new Renault, with the RS16 being launched 40 minutes later than planned due to delays finishing the car.
Follow live coverage and timing from pre-season testing here
GALLERY: Pre-season testing day one
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