Lewis Hamilton was puzzled by his slump at the end of qualifying in China, and had no idea why he was unable to challenge for pole having topped both Q1 and Q2.
The McLaren driver went into Q3 as favourite for pole following his strong performance in practice and the first two segments of qualifying, but could only manage sixth on the grid – half a second down on pole winner Sebastian Vettel's Red Bull.
"We were doing so well in practice and in Q1 and Q2," Hamilton said. "It was quite easy to be up the front. The car started bottoming a lot more in Q3 but I don't know whether that's had anything to do with the balance of the car, but I just had no more time in the car. The car was sliding a lot more.
"In Q1 and Q2 the car was even better and I really don't understand what was wrong with the car in Q3 but I wasn't able to get any more time out of it. That was me on the limit, so I don't know where the time is. We have to go and analyze it and try and find it, but I'm sure tomorrow will be a good race."
Hamilton was also outqualified by his teammate Jenson Button for the third time this year, with the reigning World Champion beating his predecessor to fifth.