- McLaren's Lewis Hamilton heads Jenson Button in practice ahead of Korean Grand Prix
- Sunday's race will England-based McLaren's 700th outing in Formula One
- Mercedes' Nico Rosberg fails to finish session after collision with Jaime Alguersuari
- Rosberg fined $13,000 for failing to report to stewards in a timely manner
McLaren will celebrate 700th Formula One races this weekend, and the team's British duo of Lewis Hamilton and Jenson Button led the field in Friday's practice ahead of the Korean Grand Prix.
Hamilton, second in Yeongam last year and world champion in 2008, recorded a lap of one minute 50.828 seconds on a wet track to head off 2009 world champion Button by 0.104 seconds.
Red Bull's Sebastian Vettel, who became the sport's youngest double world champion with a third-place finish at last weekend's Japanese Grand Prix, was third fastest . The German was 1.818 seconds of the pace set by the McLarens as he seeks a sixth consecutive pole position on Saturday.
Ferrari's defending race champion Fernando Alonso, who lost his 2005-06 record to Vettel, was fourth ahead of Red Bull's Australian driver Mark Webber in fifth.
McLaren team principal Martin Whitmarsh was delighted that the England-based marque has reached the milestone, which comes a week after Button's victory at Suzuka.
"Obviously we are very proud," Whitmarsh told F1's official website. "I think our friends at Ferrari have been around longer than us, but 700 is still an important milestone. I think it is something we are recognizing within the business.
"Apart from that clearly we have got to look forward. It would be nice to think we'll be here, still alive and competitive in another 700 grands prix's time, but it is a great achievement for the team and for the brand."
Whitmarsh said McLaren's focus was on challenging for victories in the season's four remaining races, despite Vettel, 24, having already sealed glory.
"We felt we could go into the last five races with an opportunity to potentially win some of those. Delighted, of course, to do so particularly on a great circuit like Suzuka," he said.
"It was a fantastic win from Jenson. He is driving better than ever so that was great. We've only had a few days to celebrate it, that's the trouble with winning the first of a back-to-back, but hopefully we will move on from there and be successful here."
Mercedes' Nico Rosberg was forced out of the session after colliding with Jaime Alguersuari as the sixth-placed Toro Rosso driver exited the pit lane.
The German, who was eighth fastest, was called to the stewards' office after the session and subsequently fined $13,000 --$6,500 of which was suspended -- for failing to report to them in a timely manner.
Qualifying at the Korea International Circuit will take place on Saturday, ahead of the 16th grand prix of the 2011 Formula One season on Sunday.