Romain Grosjean set the pace on the second day of pre-season Formula 1 testing at Jerez, while Lewis Hamilton's first outing for Mercedes was cut short by a crash.
Lotus driver Grosjean, who led the way in the morning, went faster on a series of short runs on the soft tyre in the afternoon.
He eventually got down to a 1m18.218s, six tenths faster than Jenson Button managed on the opening day for McLaren, before switching to longer runs focused on heavy fuel loads and the hard compound tyres.
Grosjean was the only driver in the top nine to improve in the afternoon, and with just three minutes left on the clock he brought the day to a close by stopping on track between Turns 3 and 4, bringing out the red flags.
Nico Hulkenberg also came to a halt in his Sauber before he could get back to the pits, stopping between Turns 8 and 9 after running out of fuel.
Aside from the performance of the Lotus, the main focus of the day was the plight of Mercedes.
After the team finished early on day one due to an electrical problem when Nico Rosberg was at the wheel, new signing Hamilton clocked just 15 laps before a rear brake problem caused him to crash at the Dry Sack hairpin.
Mercedes looked in to fixing the car in time to get Hamilton back out on his first day of proper testing with the F1 W04, but eventually decided against it and worked on repairs to areas including the hydraulics.
There were improvements towards the bottom of the field in the afternoon. Pastor Maldonado got up to 71 laps after a clutch problem had delayed Williams earlier on, and Giedo van der Garde found six tenths in the Caterham to end the day on a 1m21.311s.
Late on, Force India simulator driver James Rossiter returned to F1 testing duties for the first time since a run for Super Aguri in 2008.
The Briton took over from Paul di Resta with just over an hour remaining, and in 19 laps managed a best time of 1m21.273s.
Marussia's new signing Luiz Razia stopped with an engine problem in the morning. Despite the team's best effort, it was not resolved in time for him to rejoin the track.
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