McLaren duo sure of strong weekend

Both Button and Hamilton regularly topped the afternoon session as the track surface rubbered in - following a difficult earlier practice in which most drivers struggled on the extremely dusty circuit - and were classified fifth and third respectively as the session drew to a close.

The team-mates were sure, however, that the McLaren MP4-25 had closed the gap in Korea.

"We are genuinely very quick on the straights," Hamilton said. "I think everyone has dropped a bit of downforce and seem to have caught us up a little bit on the straights. But nonetheless, we are very competitive, as competitive as the Red Bulls at least."

After a disappointing Japanese Grand Prix - in which both drivers lost further ground to championship leader Mark Webber - McLaren is introducing several technical developments this weekend, including new rear wings.

"We've got a few more new bits on the car," Hamilton continued. "They were in Japan but we didn't have all the bits together to put them on, so we've finally got them on.

"We seem to be quite competitive in the middle sector, where the rear wing is working.

"But it's still very, very close. The Renault looks quick, the Ferrari looks quick and the Red Bull looks quick. The cars are fairly equal this weekend. Maybe it's really down to which driver can pull out the best time."

Despite an overheated engine that cost him over 30 minutes of track time, Hamilton's team-mate Button concurred that the new circuit played to the car's strengths.

"I had an issue this afternoon," the 2009 World Champion explained," with the car smoking and catching fire. I lost about thirty minutes in the pits with that, so it was a little bit disappointing not to do a heavy fuel run. But for me the car's working really well.

"I felt we got to grips with [the track] very quickly. We're very strong in the first sector, as most people expected, but also in the other sectors we're competitive.

"All the way through the sessions we've been competitive. One of us has pretty much been at the top end of the times. You still don't know where you stand on a Friday, but the important thing is that the feeling is good. We've made some good improvements today."

Heading into the final practice session, both drivers agreed that the track conditions had improved quickly during the day.

"The first session was very interesting," Hamilton said. "It was the dirtiest circuit I've ever been on! It was so dusty, it was incredible! So everybody was having trouble, sliding around a lot. But the evolution has been quite dramatic. People were just speeding up, just seconds per lap."

"I think it was pretty tricky initially because we had such low grip," Button concurred. "We didn't get too carried away with trying to change the balance to suit the circuit because it's changing so quickly.

"There's so much rubber going down", "I mean every session we gain two and half, three seconds, so it's massive! I don't think it's going to stop either."