Despite Ross Brawn's claim that Rubens Barrichello has been "unlucky" not to win a Grand Prix this season, there is mounting speculation that the team is favouring Jenson Button. The situation was hardly helped yesterday, when, during the Spanish Grand Prix, the team opted to switch Button from a three to two-stop strategy, a move that ultimately proved decisive when the Briton took his fourth win of the season.

However, at the post race press conference, when asked if the strategy change, which effectively handed Button the win, echoed what happened at Ferrari, particularly in Austria 2002, when team orders favoured his teammate (Michael Schumacher), Barrichello pulled no punches, especially when asked if it might happen again.

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

Teammate Button was quick to step in, telling the media, and Barrichello: "I'm going to answer this a bit as well because this affects me. Our strategy said that a three stop was quicker, full stop."

"It's true," Barrichello continued, "it's much more different than it used to be at Ferrari. We have a much more friendly situation, so I'm not sitting down on the side blaming this or that. The race was finished half an hour ago and that's the way it went. There's no way I'm going to be crying here and saying I should have done this or that. It's in the best interests of myself to learn what went wrong today because I had the ability to win the race but I didn't and this is a full stop.

"Jenson is on a flyer and he's doing very well. I think this weekend was really good for me because I worked quite hard on all the set-up and everything. We both learned to get better, we're pushing each other very well. There's a bit more pressure on my side, obviously, because he's won four races and I've won nothing but I'm there, I'm working and I won't stop working.

"I'm definitely raising my hands to the sky to give thanks because this is a great car. It was not long ago that people were putting flowers on my grave and saying 'thank you very much for your job' and so on. So I'm here, very much alive and happy and I'm going to make it work. It's as it was some years ago but with a much more friendly atmosphere."

However, the Brazilian subsequently told a SpeedTV reporter that he would "hang up his helmet" if he suspected the Brackley team was favouring Button. "I'm sure everything is OK," he said, "but if I get the slightest sniff of the fact that they have favoured Jenson, I will hang up my helmet tomorrow,.

On Friday, Brawn, who was Technical Director and strategist at Ferrari when Barrichello partnered Schumacher, said: "I'd love to see Rubens win a race and see his crew win a race because it would be great for the team."

When asked about team orders, following yesterday's race, Brawn told reporters: "The strategy change was my decision. The engineers and drivers pool their information and make their recommendations but I make the call in the pit lane and, good or bad, we stand by it. If Rubens hadn't had his tyre problem, it would have been incredibly close."