Formula One:A late blast from Formula One world champion Sebastian Vettel deposed Fernando Alonso from the top of the timesheets at the end of the first day of the penultimate pre-season test in Barcelona.
Vettel is the first driver this year to end a test day out in front for the second time as the initial seven so far - three in Valencia and four in Jerez - had resulted in seven different front-runners.
Just when it appeared as if Ferrari's Alonso was poised to take the honours at the Circuit de Catalunya, Vettel - seemingly on the fast supersoft tyres - put in a lightning lap to finish quickest by over a second.
Vettel posted a time in his Red Bull of one minute 24.374secs, just over four seconds slower than team-mate Mark Webber's pole position lap in last year's Spanish Grand Prix.
The German only managed 37 laps overall following a couple of minor offs in the morning which prompted his team into making lengthy yet necessary checks throughout the lunch and the afternoon.
Despite the quick lap at the end, it was a frustrating day overall for Vettel who said: "Unfortunately, we didn't complete many laps today as we had a long break - longer than expected.
"It wasn't anything big - nothing broke - but at the test if you think there might be a problem then you'd rather take the car apart and check.
"The boys did their best and we still got some runs towards the end of the day - not as much as we'd like, but the car feels good and hopefully we'll do more tomorrow."
Alonso's best lap was 1.111secs behind Vettel, coming at the end of a morning session that had started on a wet track following heavy rain yesterday.
Toro Rosso's Jaime Alguersuari and Sauber's Kamui Kobayahsi were third and fourth quickest separated by just three thousandths of a second.
McLaren again went about their business quietly in their radical MP4-26, with Jenson Button completing 77 laps, just under two seconds off Vettel, but perhaps more realistically 0.8secs down on Alonso.
Technical difficulties meant Paul di Resta only completed 26 laps in his Force India, but still managed sixth quickest with a time of 1:26.575.
Williams' Rubens Barrichello, who spent most of the afternoon in the garage as the team changed the car's Cosworth engine, was down in seventh, followed by Mercedes' Michael Schumacher in eighth.
Hispania's Narain Karthikeyan, using last year's car, was ninth, amassing a day high 116 laps along with Virgin's Jerome D'Ambrosio in 11th, the duo sandwiching Team Lotus' Heikki Kovalainen.
Renault duo Vitaly Petrov and Nick Heidfeld finished at the bottom of the standings in 12th and 13th due to a problem with KERS which took most of the day to solve, limiting the duo to predominantly pit-stop practice.
Times
01. Sebastian Vettel Red Bull-Renault 1:24.374 37 laps
02. Fernando Alonso Ferrari 1:25.485 + 1.111 101 laps
03. Jaime Alguersuari Toro Rosso-Ferrari 1:25.638 + 1.264 57 laps
04. Kamui Kobayashi Sauber-Ferrari 1:25.641 + 1.267 78 laps
05. Jenson Button McLaren-Mercedes 1:26.365 + 1.991 77 laps
06. Paul di Resta Force India-Mercedes 1:26.575 + 2.201 26 laps
07. Rubens Barrichello Williams-Cosworth 1:26.912 + 2.538 52 laps
08. Michael Schumacher Mercedes 1:27.512 + 3.138 90 laps
09. Narain Karthikeyan HRT-Cosworth 1:28.393 + 4.019 116 laps
10. Heikki Kovalainen Lotus-Renault 1:30.065 + 5.691 54 laps
11. Jerome D'Ambrosio Virgin-Cosworth 1:30.950 + 6.576 116 laps
12. Vitaly Petrov Renault 1:35.174 + 10.800 20 laps
13. Nick Heidfeld Renault 1:44.324 + 19.950 27 laps