Jenson Button admitted he did not expect to be able to qualify so high up on the grid for the Singapore Grand Prix after a difficult Friday.

The McLaren driver lost a lot of valuable track time in the opening day's practice following a problem with his gearbox which meant he was unable to complete long runs. That means Button will start tomorrow's race without knowing how well the tires will behave in the race. The Briton was nonetheless pleased with his performance in qualifying and conceded he did not expect to be so strong.

"I think last night I didn't expect to be here," said Button. "We made a lot of changes overnight and we got quite a lot of improvements. The pace was good all day.

"We found it a little bit difficult in qualifying to get the tires working for a whole lap: if had them working in first sector they had gone off in third. We had to do a reasonably slow out lap, but maybe I got too excited and pushed too hard in the first sector as the tires were off in final sector.

"I'm happy to be third, on the clean side of the track. The worry is tomorrow as haven't driven with heavy fuel."

He added: "I didn't get much running yesterday, so I am pleased to be in top three and it is a good position for the race tomorrow."

Button's teammate Lewis Hamilton will start from fourth position.