Leader of the pack: Button lords it with Vettel and Trulli [GALLO/GETTY]

The 29-year-old Button, who won the season-opener in Australia last weekend on Brawn's debut as heirs to departed Honda, will have Toyota's Italian Jarno Trulli alongside on the front row.

Toyota's Timo Glock and fellow-German Nico Rosberg, in a Williams, will fill the second row for what could be a wet and chaotic race that is scheduled to end in the twilight.

Big guns fail to fire

As in Melbourne, the grid again had an upside-down look with last year's big guns well down the pecking order.

The pole was the fifth of championship leader Button's roller-coaster Formula One career and the first time he had done it twice in a season.

The Briton has already scored more points this year than in the past two.

An hour after qualifying had finished, torrential rain lashed the paddock with flashes of lightning across the darkened skies and thunder crashing around the circuit.

"We've got a lot of thinking overnight to put a plan together if it is wet," said Button, who took the first podium finish of his Formula One career at Sepang when he came third for BAR-Honda in 2004.

"We haven't run this car yet in the wet so it's going to be interesting."

Breakthrough

Toyota have yet to win a race since their debut in 2002 but Trulli, who finished third after starting in the pit lane last weekend, showed that they are closer than ever to the big breakthrough.

"We have a car to fight for the podium and then our aim eventually will be to win a race during the season."

"It doesn't matter if it is me or Timo."

Germany's Sebastian Vettel was third fastest and Button's Brazilian team mate Rubens Barrichello fourth in qualifying but both have penalties.

Red Bull's Vettel was handed a 10-place penalty for a collision with BMW-Sauber's Robert Kubica in Australia while Barrichello drops five places for a precautionary gearbox change after Friday practice.

Cold comfort for champ

Hamilton, at the centre of a storm this week after being stripped of the third place he had gained from Trulli in Melbourne by "deliberately misleading" the stewards, qualified 13th but will start one place up the grid thanks to Vettel's penalty.

Champions Ferrari had a self-inflicted nightmare, with Brazilian Felipe Massa qualifying 16th after a team blunder in assuming wrongly that he had done enough to reach the second session.

Ferrari have yet to score a point this year.

"The team thought it was really enough to be inside the 15, maybe I thought it was as well to be honest," said Massa of his time in the first session.

"When I started to drop (down the order), it was impossible to go out again as there was no time to do another lap."

Team mate Kimi Raikkonen, winner in Malaysia last year, qualified ninth but starts seventh after the penalties are taken into account.

The top 17 in the first session were all quicker than Massa's 2008 pole position of one minute 35.748 seconds, with Renault's double world champion Fernando Alonso only just sneaking through.