Sebastian Vettel led his third practice session of the Singapore weekend, although the hour was cut short after Vitaly Petrov brought out a red flag two minutes from the end. The Caterham driver stopped in the pitlane, but he wasn't the only one struggling. Mark Webber got a puncture from hitting the wall, whilst Timo Glock came to a halt on track with throttle trouble. Lots of work to be done ahead of qualifying!