• Jerez Test, Day One

Button fastest on opening day

Jenson Button set the quickest time of the first day of testing at Jerez as Mercedes was forced to abandon running after completing just 14 laps.

Button set a best time of 1:18.861 on a run in the final ten minutes of the opening day which put him over 0.8s clear of the rest of the field. The positive time - set on hard tyres - was in contrast to McLaren's morning troubles as Button stopped on track after just three laps due to a fuel pump problem; the delay keeping him in the garage until the mid-afternoon and accounting for his relatively low total of 35 laps for the day. The fuel pump issue was similar to the one that brought Lewis Hamilton to a halt in Abu Dhabi despite the component being a new design.

Mark Webber had gone fastest not long before Button set his time and ended the day second on a best of 1:19.709. Webber's best came on the medium compound Pirelli's during a more productive day for Red Bull as it completed 71 laps with the RB9.

Romain Grosjean was third quickest after being the first man to dip under the 1m20s barrier as he set a time of 1:19.796. His time beat that of Paul di Resta who had set the fastest time of the first morning of testing after clocking a 1:20.343. With no official lunch break in the day's running schedule, di Resta set a time just 0.058s quicker than Daniel Ricciardo just before 1300 local time (1200 GMT). Force India also ended the day with the most laps completed as di Resta clocked up a total of 88.

Ferrari's new F138 enjoyed a relatively trouble-free day as Felipe Massa completed 62 laps with a best time of 1:20.536. That time was less than 0.2s quicker than Nico Hulkenberg on his first outing for Sauber.

With Button having caused the first red flag of the day, Nico Rosberg was responsible for the second as his Mercedes came to a halt between turns 11 and 12 having completed 11 laps. Rosberg was quickest by 0.762s when he became the second car to stop on track in the opening 90 minutes with flames spitting from the rear of the W04, and his time was only bettered by di Resta and Ricciardo by 1300. However, as improvements eventually knocked Rosberg down to eighth quickest during the afternoon, Mercedes admitted a wiring loom fault needed fixing and that it would be modified for Wednesday.

Pastor Maldonado was fourth quickest during the morning and unsurprisingly the most productive driver early on as he completed 52 laps in the updated FW34. Williams is running its 2012 car to evaluate the new Pirelli tyres but does have some of its 2013 bodywork to test too, and Maldonado enjoyed a quieter afternoon as he finished the day two seconds off the pace. The most obvious addition to the FW34 was a vanity panel covering the car's stepped nose.

Marussia and Caterham launched their respective new cars in the hour before the light at the end of the pit lane went green, with the Caterham retaining the stepped nose from the CT01 on its 2013 design. As Marussia's only confirmed driver, Max Chilton was in the car on the opening day but caused a red flag in the afternoon after the MR02 ended up in the gravel with a bent right rear suspension. The team said the issue needed investigating and called time on its running an hour early.

Tuesday times

Nico Rosberg's running came to a premature end after just 14 laps © Getty Images

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