Red Bull driver Mark Webber set the pace in cold and wet conditions on the first day of the final Formula One preseason testing session, edging just ahead of Lewis Hamilton of Mercedes.
After Ferrari's Felipe Massa stopped on the track with less than half an hour to go, Webber out-dueled Hamilton as they clocked flying laps just before the session ended.
The 36-year-old veteran put in a day's quickest lap of 1 minute, 22.693 seconds, leaving Hamilton's best effort less than two seconds behind.
Webber said that Red Bull was pleased with the run-up to the new season, when teammate Sebastian Vettel will seek to defend his world title.
"I think our preparation is a lot better than last year when we started the season scratching for podiums in the first five, six, seven races," Webber said. "We had more challenges to understand the car last season. This year we know it well because it is not a huge change from last year.
"But it still remains to be seen if we can win at different venues, and that's what F1 is about."
The only downside to Red Bull's session, Webber said, was the fact that the rain and low temperatures seen both last week in northeastern Spain and on Thursday don't reflect a typical race.
Webber and the rest of the grid open the season in his native Australia at the grand prix in Melbourne on March 17. Webber has nine career wins, but none have come in front of his home fans.
"I enjoy running at Melbourne. I am fast there. I just need to keep knocking at the door," he said.
Jean-Enric Vergne of Toro Rosso recorded the third fastest lap, in front of rookies Valtteri Bottas of Williams and Esteban Gutierrez of Sauber.
Hamilton was the busiest driver and completed 113 laps, one more than Massa. Sergio Perez, who took Hamilton's spot at McLaren this offseason, was the only other to reach the 100-lap mark.
"The track started out really wet this morning, but thankfully the conditions dried out later on and we were able to complete some proper running," Hamilton said. "It felt good to work through the race simulation this afternoon, both to get myself back in practice and to put valuable miles on the car."
Steady showers fell through the morning and intermittently through the early afternoon, with temperatures hovering above 10 degrees (50 F).
Most of the field dealt relatively well with the slippery surface as they got another go on the wet tires for this season. Only Lotus' Romain Grosjean and Gutierrez spun off course and provoked red flags before Massa's late stoppage.
Massa, who could do no better than the eighth fastest time out of 11 drivers, at almost five seconds behind Webber, said he intentionally ran out of fuel in order to make sure "everything was working well."
It was the first full race simulation of the preseason for Massa, who stuck to the same message that teammate Fernando Alonso has repeated - of being cautiously optimistic for the upcoming campaign.
"It was an important day. I ran my first full race simulation and the car was good on wet," the Brazilian said. "The wind was very strong and had an impact on the car, but its stability was good. I am confident and the feeling is good compared to last season at this point. But until you are in qualifying with all the cars on the same fuel and tires it is difficult to tell."
Force India brought an end to its audition for a partner for Paul Di Resta by choosing former driver Adrian Sutil over Jules Bianchi. Sutil, who raced with Force India from 2007-11, will test on Friday.
Last year's runner-up Alonso and fellow contender Jenson Button of McLaren, among others, will also take the wheel on Friday.
Testing continues through to Sunday.
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