Button: I found it another world and disconcerting

Button spent almost an hour and a half, 20 laps around the Circuit de la Sarthe, in the #11 SMP Racing BR Engineering BR1-AER for the first time. He will share the car with former F1 driver Vitaly Petrov and Mikhail Aleshin.

Speaking to reporters at the end of the day Button reflected, "I was reasonably happy, but in the morning I found it another world - driving around here in a car I don't really know. I found it quite disconcerting. But we made some good changes over lunch."

"I was much happier with the car in the afternoon. High speed, good confidence and the braking was much better too. A lot of the corners here are very tight and they come upon you very quickly, which is very different from what I'm used to."

"I definitely got to grips with it in the afternoon, much happier. But you always want more running, and new tyres. Hopefully, we get some good laps in the Wednesday tests."

Co-driver Petrov was fifth quickest with a best time of 3:21.603, which compared to Button's best of 3:24.002 which he set late in his stint. However, the team were denied maximum track time due to technical issues.

Button explained, "We lost a lot of time because of a sensor issue this morning, so we lost a couple of hours just in the garage, it was a shame. Then we had another small issue after lunch, so our track on time was quite limited."

"I only ran one set of tyres, not a new set. I think I did 20 laps, but I learnt a lot. This place is all about building confidence and gaining time."

"You can go out and be as quick as you can, but there's a big chance you'll go off. You've really got to respect this circuit. It's tough. I feel very confident now at the end of the day, but I'd rather have had another 50 laps," added Button who this year is also campaigning the Super GT series in Japan this season.

Alonso topped the timesheets in the #8 Toyota Gazoo Racing at the end of the practice day on Sunday. The Le Mans race weekend takes place on 13-16 June.