AUSTIN, TEXAS, Nov 16, 2012 (AFP) - Defending world champion Sebastian Vettel shrugged off technical problems as he dominated Friday's opening day of practice ahead of this weekend's United States Grand Prix for his Red Bull team as he bids to clinch a third successive title.
Vettel, who was fastest in the morning free practice session ahead of Lewis Hamilton of McLaren, was quickest again in the afternoon ahead of his Red Bull team-mate Mark Webber as the champion team stamped their authority on the action.
The 25-year-old German clocked a best lap of one minute and 37.718 seconds to top the times in the second session to outpace Webber by seven-tenths of a second despite missing much of the afternoon running due to a water leak.
"It reduced the running time, but it was not too much of a worry," he said.
"And there is a day ahead for practice so I am sure we are ok. We are in the right place now."
He added: "We got into the rhythm really quickly. This afternoon we had a bit of a problem and did not run as much as we would have liked to, but nevertheless we had two good runs - so we are well prepared for tomorrow."
Although Vettel was fastest in both sessions, he said he believed the opening day's action could end up being entirely irrelevant by time Sunday arrives.
"On Friday, you need to be careful and the fact it is so slippery can make a big difference," he said.
"I think there were one or two surprises today - and we will see what happens tomorrow. The track will constantly improve. It is important that we are among the guys at the top, and we'll try and improve the car and go from there."
Vettel's only remaining title rival, two-time former champion Fernando Alonso of Ferrari, was third fastest ahead of Hamilton and his McLaren team-mate and fellow-Briton Jenson Button.
Alonso's Ferrari team-mate Felipe Massa was sixth in the second session run on the 'green' new Circuit of the Americas 25 kms outside downtown Austin ahead of German Nico Rosberg of Mercedes.
Bruno Senna of Williams was eighth fastest ahead of Kamui Kobayashi of Sauber and retirement-bound Michael Schumacher in his Mercedes.
Webber was fastest for most of the afternoon before Vettel's re-emergence late in the session to trim the fastest time of the day as they both proved they have the pace to enjoy Formula One's return to America for the first time in five years.
Earlier, Vettel topped the times in the opening session almost too easily.
The German, who needs to outscore nearest rival two-time champion Spaniard Fernando Alonso by 15 points to become Formula One's youngest triple champion, produced his customary blistering pace in his first run at the brand new circuit.
In his 100th Grand Prix event, Vettel looked ominously quick as he clocked a best time of one minute and 38.125 seconds around the 5.516-k,ms track, a signal that there was more to come -- and one he delivered on.
Kimi Raikkonen of Lotus, winner of the Abu Dhabi Grand Prix two weekends ago, was first out on to the 'green' circuit on a morning of many minor incidents as the drivers learned their way round the spectacular sweeping track.
Nico Hulkenberg of Force India was the first driver to enjoy a major spin, but most of the field endured a variety of unscheduled excursions off the ashphalt, notably at Turn 19 where Hamilton, Vettel and Massa all slithered wide as they under-estimated the fast left-hand corner.
Hamilton looked likely to be the early session-topper until, with only three minutes to go, Vettel blitzed to his fastest lap and left his rivals with little chance to respond and then returned in the afternoon to deliver more of the same.
|1||1||Sebastian Vettel||Red Bull Racing||1:37.718||17|
|2||2||Mark Webber||Red Bull Racing||1:38.475||0.757||36|
|15||16||Daniel Ricciardo||Toro Rosso||1:40.435||2.717||30|
|16||17||Jean-Eric Vergne||Toro Rosso||1:40.516||2.798||32|
|17||12||Nico Hulkenberg||Force India||1:40.700||2.982||34|
|18||11||Paul di Resta||Force India||1:41.430||3.712||35|
|23||22||Pedro de la Rosa||HRT||1:44.453||6.735||16|