Jenson Button made it three wins from four races to strengthen his early grip on the Formula One world championship with victory in a heat-sapping Bahrain Grand Prix.

After wins in Australia and Malaysia, Button's Brawn GP car simply had too much brute force for his rivals to seriously compete with the 29-year-old Briton.

Last Sunday's Chinese Grand Prix winner Sebastien Vettel had to settle for the runner-up spot, with pole-sitter Jarno Trulli third in his Toyota.

It leaves the Japanese manufacturers still searching for their first win after 127 grands prix.

Once the five red lights disappeared to signal the start of the 57-lap race, it was Timo Glock who held sway over his team-mate.

The young German was quicker off the line than the veteran Italian, and by turn one had grabbed a lead he held for a mere 11 laps.

That was due to the fact he was the lightest on fuel of the entire field, and was the crucial reason he could only finish seventh come the chequered flag.

The surprise was the sight of Trulli, three laps heavier on fuel, pit just one lap later than Glock, relegating both men back into the traffic of a congested mid-field.

It paved the way for Button to make hay, with the pit wall telling him to "give it everything you've got" - which he duly did for three laps.

When he made his first call into the pits, he emerged ahead of the 34-year-old Trulli, keeping faith with the supersoft tyres that had served him well to that point.

In contrast, Trulli had switched from the soft tyres to the primes which were running close to a second per lap slower, as was proved during the middle stint of the race.

By the time of the second stop at the end of lap 37, with both men in, Button had opened up a cushion of almost 18 seconds.

Trulli switched back to the soft tyres, whilst Button was forced to take on the prime, and the duel appeared to be on between those two drivers.

However, Vettel was to prove a major player following an unusually poor start from his perspective, although he was the heaviest with fuel of the top five.

Starting from third on the grid he was passed by both Button and

reigning world champion Lewis Hamilton, who used the KERS boost button to pass the German and his fellow Briton on the run down to the first corner.

It was a position Hamilton was soon to relinquish, though, due to the superiority of the Brawn over the McLaren, with Button making his move on the 24-year-old at turn one of lap two.

As for Vettel, he was forced to hang onto the exhaust of the duo and hope two rounds of pit stops would work in his favour.

And they did as Vettel edged out Hamilton at the first and then Trulli at the second.

The latter will have been especially gratifying as he found himself held up by Trulli for 18 laps in the middle stint, even though he was on the marginally quicker softer tyres.

Over the closing stages the tables were turned as Trulli was unable to make any kind of move on Vettel, despite running closely behind the Red Bull.

Come the finish, Button clinched his victory by 7.1secs over Vettel, with Trulli third, followed by Hamilton who was 22 seconds down, but who grabbed his best result of the season.

Rubens Barrichello, who worked on a three-stop strategy, finished fifth, helping Brawn to a 22.5 point lead over Red Bull Racing.

Finally, Ferrari have points on the board as Kimi Raikkonen came home sixth, ensuring the team avoid the worst start to a season in their history.

Behind Glock, Fernando Alonso in his Renault was eighth of the 19 cars that remarkably finished in 36 degree heat, with Williams' Kazuki Nakajima the only casualty.

"This was a tough race for us," said a smiling Button. "This weekend we've not had the pace of the first few races for whatever reason. I guess these guys (Red Bull and Toyota) have caught us.

"But the start was important, and I had a good one. When I passed Lewis at the start of turn two, that was the move that really made the race for us.

"So I'm very happy. This race win is the best of a lot. To come away with this win is great."

Vettel was content enough with second as he said: "I'm very pleased we've got some points at the end of a difficult race.

"I was surprised at the start because I was passed by Lewis - I guess he pressed his special button (KERS).

"I then followed him early on, and because of the tyres it was difficult to pass.

"But I got past him at the first round of pit stops, and then the same with Jarno at the second.

"Towards the end I had Jarno in my mirrors, but I made no mistakes and I finished second."

Trulli was dejected but confident the team will come again.

"I'm disappointed because I wanted to get Toyota's first win, but I want to thank the team because they've done a good job," remarked a magnanimous Trulli.

"Let's wait to fight again at the next race."

As for Hamilton, he was happy enough with fourth, appreciating he could did not have the pace of the front three.

"I'm delighted considering we started fifth," said Hamilton.

"We had a great start, but it was so hard to keep up with the Red Bull and the Toyotas and Brawn. It was impossible.

"We've got to keep pushing, but this is good for the team."