Perez under investigation for Q2 lap

Sergio Perez is under investigation for improving under yellow flags on his final lap in Q2 during qualifying for the Singapore Grand Prix.

Late in the second part of qualifying, Romain Grosjean lost control of his Haas at Turn 10 and went backwards into the barrier, with double waved yellow flags being used as the clock ticked down in the final 20 seconds. Immediately after Grosjean's crash, Jenson Button stopped at Turn 16 having clipped the wall.

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Many cars were on their final laps in the session and backed off as a result of the yellow flags, but Perez was outside the top ten and set to be eliminated. The Mexican was shown passing Esteban Gutierrez under the yellow flags for Button's car before completing his lap and improving enough to progress to Q3.

With Perez's lap demoting Valtteri Bottas to 11th and Felipe Massa to 12th, both Williams drivers failed to progress. Following the end of the session - in which Perez finished 10th - the Force India driver was called to the stewards as he is alleged to have failed to slow at Turn 9 and Turn 10.

Perez himself believes he lifted off enough in that particular sector, while saying he only passed Gutierrez because the Haas moved out of his way.

"Basically it was a very tricky session, I think I had three yellow flags on my lap," Perez said. "So I was lifting a lot, I lost around 0.6s with yellow flags. In the end with Esteban he was very slow so I managed to keep the line and he was obviously on a very slow lap, so he opened up the racing line. On that certain occasions I think I lost 0.4s because I had to lift.

"I think we have all the data that backs me up, so there is no issue at all.

"At the end of the day you have the telemetry that the stewards will check and I have no problem with it."