Nico Rosberg again announced himself as a potential threat to take pole position at round two of the F1 world championship in Malaysia after pushing his Williams-Toyota to the head of the free practice times on Saturday morning.
The German has now headed five of the six free sessions held in 2009, but will want to convert that apparent advantage when it matters by putting Williams back on pole position - for the first time since the 2005 European GP - in the knock-out qualifying on Saturday evening. Having hovered around the leading times, Rosberg produced a late lap that proved to be the only one good enough to dip below the 1min 36secs barrier, and go a tenth clear of his nearest rival.
Mark Webber's 1min 36.048secs effort came up 0.108secs shy of P1, but the Australian will be buoyed sufficiently to believe that he may have a shot of reprising his front row slot from 2004. Indeed, Red Bull continued to show that it will be a contender for the sharp end, as Sebastian Vettel posted the sixth best time, putting him behind Felipe Massa and the Toyotas of Jarno Trulli and Timo Glock.
Ferrari also suggested that it will be a factor for qualifying, with Kimi Raikkonen, overall pacesetter on day one, slotting into seventh spot in a session where the Scuderia is not known for pushing to the maximum. The Finn ended the hour a little over three-tenths from Rosberg's pace, and ahead of the remaining 'diffuser' cars of Kazuki Nakajima and Melbourne frontrunners Rubens Barrichello and Jenson Button.
Button had topped the times mid-session, but the rash of faster laps in the closing stages pushed the two Brawns further down the order then their true performance probably warrants. It was notable, however, that the two white machine were blowing smoke from their exhausts, although the team insisted that it was merely the result of over-filling the oil tanks rather than any inherent engine problem. Barrichello is already facing a mandatory five-place qualifying demotion having had to change his gearbox overnight.
Behind the Brawns, Robert Kubica gave BMW Sauber a minor fillip by posting the eleventh best time after the team had languished at the foot of the times on Friday. Again, the team maintained that that was the result of focusing entirely on race set-up on the opening day, although Nick Heidfeld would have hoped to climb higher than 15th ahead of qualifying.
The two BMWs sandwiched the McLarens of Lewis Hamilton and Heikki Kovalainen, as well as Fernando Alonso's Renault, the Spaniard still struggling with the effects of an ear infection and failing to rise above 14th. A late improvement, however, was enough to lift him above team-mate Nelson Piquet Jr, who had occupied a top ten spot until the closing stages of the session.
Force India and Toro Rosso brought up the rear of the field, with Adrian Sutil and Giancarlo Fisichella book-ending the two Sebastiens, with Buemi ahead of Bourdais.. There was no repeat of the Italian's FP2 accident in a largely uneventful hour.