Mark Webber became the third different F1 pacesetter of the 2011 Singapore Grand Prix weekend after topping the floodlit Saturday practice session, but knows that at least a couple of drivers could have usurped him had luck gone their way.
The Australian kept Red Bull Racing on top of the pile following team-mate Sebastian Vettel's frontrunning performance on Friday night, but the championship leader appeared on course to beat his eventual 1min 46.081secs benchmark when he was held up by Pastor Maldonado's Williams. Vettel wound up only third fastest, separated from his team-mate by Jenson Button's McLaren, having looked the most potent on the harder of the two Pirelli compounds.
Button's performance was the perfect riposte after a troubled Friday but, despite getting to within 0.027secs of Webber's best, the Briton reported that he was still not happy with the balance of his MP4-26. McLaren team-mate Lewis Hamilton was two places further back, having endured an early trip down an escape road, and then taking flight over one of the Marina Bay circuit's contentious kerbs.
Between the two silver machines, Fernando Alonso - a double Singapore GP winner - put his Ferrari into fourth place, just over three-tenths off Webber, while team-mate Felipe Massa was a long way off the pace in eighth.
The Brazilian could not get within two seconds of his team-mate, let alone Webber, after spinning and had both Mercedes slotting in between himself and Hamilton. Nico Rosberg and Michael Schumacher proved evenly matched, but ended the hour-long session 1.7secs off the pace. The top ten was completed by Kamui Kobayashi's Sauber and the Force India of Adrian Sutil, with the second Sauber of Sergio Perez next up, suggesting that the two teams could continue to battle over sixth place in the constructors' championship.
Sebastien Buemi ended the session in twelfth spot, recovering his composure after Friday's off, but Toro Rosso team-mate Jaime Alguersuari gave the engineers something to do before qualifying after launching his car over the kerbs. Paul di Resta, the Williams of Pastor Maldonado and Rubens Barrichello and the Renaults of Vitaly Petrov and Bruno Senna - who also ran out of road early on - filled the void between the two Toro Rossos.
As has become expected, Heikki Kovalainen led the backmarkers, fully two seconds from Alguersuari, with Jerome d'Ambrosio and Daniel Ricciardo both getting the better of the second Lotus of Jarno Trulli, who slotted in ahead of Timo Glock and Tonio Liuzzi.