Highlights - Italian Grand Prix
Rubens Barrichello headed Jenson Button for a Brawn one-two in a tense Italian Grand Prix as the Englishman scored his first podium finish in six races.
McLaren's Lewis Hamilton, who started on pole but was beaten on strategy and pace, lost third place when he crashed on the last lap trying to catch Button.
Ferrari's Kimi Raikkonen took the place ahead of Force India's Adrian Sutil.
Brawn's title rivals Red Bull had a bad day as Mark Webber crashed on the first lap while Sebastian Vettel was eighth.
Button has had his championship lead cut by two points to 14 from second-placed Barrichello, while Vettel sits 12 points behind the Brazilian with Webber 2.5 points behind his team-mate in fourth.
Forty points are available now with four races remaining.
Two-time world champion Fernando Alonso pushed hard throughout the race to finish fifth, just ahead of McLaren's Heikki Kovalainen.
It was great to have such a good start. The first lap made my race
After starting back in 15th, Nick Heidfeld did well to score two points for struggling BMW Sauber with a seventh place.
Hamilton was eventually classified in 12th after dramatically crashing out on the exit kerb of the first Lesmo on the last lap having been breathing down Button's neck for the final third of the race as he desperately tried to get in a position to overtake his compatriot.
The 13th grand prix of 2009 was a tale of two races within a race - pole-sitter Hamilton trying to gain enough time to stay ahead of the Brawns knowing he needed to stop twice, while they competed against each other and sought to keep Hamilton at bay.
In-form Barrichello - who claimed his second win in three races - made a brilliant start, jumping into fourth from fifth as Kovalainen slipped down the field despite possessing a Kers power boost button.
The Brazilian built on that move with an aggressive first lap and that early period was also critical for Button.
He swiftly produced a clever manoeuvre on struggling Finnish driver Kovalainen, overtaking on the inside of the second Lesmo to put him into a truly competitive position.
"Our main competitor, we felt, was Kovalainen," said Button. "But he had a very tough first lap and we both got past him which was very, very important."
Seven out of last 10 Italian Grands Prix have been won from pole but, while Hamilton opened up a decent gap before his first pit stop, the Brawns stayed well in touch as they ran solidly in fourth and fifth.
Second-placed Raikkonen had jumped Sutil at the start but both drivers were on a two-stop strategy, meaning they were effectively without a chance of winning.
Hamilton's car did not, ultimately, have the pace of the Brawns whose strategy - fuelling heavier in qualifying to use just one stop in the race itself - proved to be a shrewd move.
Italian GP top three drivers interviews
The lead swapped between Hamilton and Barrichello, but as their differing pit-stop strategies played themselves out, it became quickly apparent that the Brawns had the edge and Hamilton emerged from his final stop in third place.
The world champion was not about to give up, and he closed on Button over the remaining laps of the race.
Heading into the last lap, Hamilton was about a second behind Button and still still striving to close the gap when he pushed just a bit too hard, dropped a rear wheel too far on to the kerb, and spun across the track before smashing into the barriers on the inside.
The veteran Brazilian, meanwhile, was firmly in control in the latter stages with a relatively safe gap between himself and Button - while his decision to stick with an engine which had briefly caught fire at the last race in Belgium was fully vindicated.
"It feels great. I have no words," he said. "At 37 I'm driving better than I ever have.
"I had a tough night, we didn't know if the gearbox would be OK and there are some concerns. But it should last [for the rest of the season].
"It was great to have such a good start. The first lap made my race. There will be times when we don't have to worry about the Kers cars, but with the straight lines here you do."
The championship battle now looks to be a straight fight between two team-mates - a rare thing in a sport where one driver is usually favoured over the other as the season pans out - after a poor race seemed to blow any title hopes for struggling Red Bull.
Webber, who started 10th, went off at the Della Roggia turn after tangling with BMW Sauber's Robert Kubica in what the Australian described as a 'racing incident' - meaning it was not the Pole's fault as he was genuinely challenging for position.
"This gives [my championship chances] a blow, for sure," said Webber. "I haven't scored points in three races, though this is my first DNF [did not finish] of the season.
"We've still had a great middle run in the championship but we need to bounce back from this. We need to finish the season as strongly as we can but it's been a tough period for us."
Button's finish, which clinched Brawn's fourth one-two of the year, was a decent response to critics who have been constantly questioning whether he has been struggling to deal with the pressure of leading the championship after a relatively barren recent run.
"It's nice to be back up here," said the 29-year-old, who won six of the season's first seven races but had only collected 11 points in the five before Monza.
"I'd like to be where Rubens is sat but he did a better job today. I've lost two points to Rubens but gained seven on Vettel.
"We're going to take it I'm sure right down to the wire...for me it was a great result."
German driver Sutil collected his first points of the season by finishing fourth while also handing increasingly-impressive Force India a consecutive second place over the past two races.
Team-mate Tonio Liuzzi, making an impressive debut for the team, was challenging in a points position before he was forced to retire with a mechanical problem.
"It's been another great weekend for Force India," said team owner Vijay Mallya.
"We thought the podium would be a dream here, going into the weekend, and at the end of the race we were less than half a second away."
Giancarlo Fisichella finished just outside the points in ninth on his Ferrari debut.