Rubens Barrichello has threatened to quit Formula One if he senses team orders coming into play in his fight for the title with team-mate Jenson Button.

For the fourth time in five races this season, Button stood on the top step of the podium, spearheading a Brawn GP one-two at today's Spanish Grand Prix.

It was the ninth successive race a driver has won from pole at the Circuit de Catalunya in Barcelona, although this was no routine run from start to finish as in the past.

Instead, there was an undercurrent of discontent from Barrichello at the prospect Button had been favoured ahead of himself.

After being passed by third-on-the-grid Barrichello on the run down to the first corner, Button then spent the first 18 laps behind the Brazilian.

When he pitted, he had been informed by his team the lap previously that he was being switched from a three-stop to a two-stop strategy as boss Ross Brawn attempted to cover all bases.

There was no such call for veteran Barrichello, who remained on a three-stop plan, which cost him the victory.

Technical guru Brawn, who made the call to change Button's tactics, claims Barrichello lost out due to a third set of soft tyres that strangely lacked the pace of the previous two.

The 36-year-old Brazilian, though, was clearly sore at what had unfolded as he said: "I hope the guys come back and tell me there was a small problem somewhere.

"We were both on three stops, then they changed the strategy for him, which is good for him, and good for the team we were one and two, but I'd like to understand why we changed that (the strategy).

"We'll have a meeting, and then we'll have some answers."

In light of Barrichello's experiences at Ferrari where he was clearly a number two driver and forced to bow to team orders, Barrichello then definitively outlined his position.

"If I get a whiff of team orders I will hang up my helmet on the spot," asserted Barrichello.

"I'm very experienced and if that happens I won't follow any team orders any more. I'm making it clear now so everybody knows."

Despite the problems he endured at Ferrari, Barrichello maintains the culture within Brawn is far different.

"We've a much more friendly situation, so I'm not blaming this or that, and there's no way I'm going to cry and say I should have done this or that," insisted Barrichello.

"It's in my own best interests to learn what went wrong today because I have the ability to have won the race, but I didn't.

"Jenson is on a flier, is doing very well, and obviously there's a bit more pressure on my side because he has won four races and I've won nothing.

"But I'm there working, and I won't stop working because this is a great car.

"It was not that long ago people were putting flowers on my grave and saying thank you very much for the job I'd done.

"But I'm here, very much alive and happy, and I'm going to make it work as I did a few years ago, but in a more friendly atmosphere."

Button, and in particular Brawn, both fervently dismissed the idea team orders had come into play.

"We both work closely together within the team, and there's a very good atmosphere," insisted Button.

"We're all here to win - it went my way today, and it may go his (Barrichello) way in Monaco. That's the way it is.

"He had a problem on his stint, I didn't, I made it work and I won the race, but then it could swing around at the next one.

"That's the way we go racing, the way it should be, and the way it has been for most teams in Formula One.

"I don't ever want to go down that avenue of talking about that because it is so far from the situation within our team."

As for Brawn, when asked whether team orders had perhaps crossed Barrichello's mind, he replied: "I hope not because we're not (doing that).

"I think you saw at the first corner there are no team orders as Rubens made a great start to get past Jenson.

"I'd love to see Rubens win a race and his crew win a race because it would be great for the team.

"But there's no priority being given."

A first-corner accident that wiped out Toyota's Jarno Trulli, Force India's Giancarlo Fisichella and the Toro Rosso duo of Sebastiens Bourdais and Buemi got the race off to a spectacular start.

There was further pain for McLaren and Ferrari as Heikki Kovalainen and Kimi Raikkonen both retired, whilst world champion Lewis Hamilton was ninth, finishing a lap down on Button.

Behind the Brawns came the Red Bull Racing pair of Mark Webber and Sebastian Vettel, with Renault's Fernando Alonso fifth.

Ferrari's Felipe Massa finally ended his personal points drought with sixth, albeit after losing two places in the final three laps after being told to slow down as there was a danger he would run out of fuel.

BMW Sauber's Nick Heidfeld and Nico Rosberg in his Williams completed the top eight.