The 'team orders' saga has hotted up even more, with Rubens Barrichello threatening to quit Brawn GP if he is again the victim of team orders.

After the Spanish grand prix, the Brazilian veteran played down any comparison between the situation in Barcelona and his six years as Michael Schumacher's number two at Ferrari.

But with Ross Brawn the common denominator, a frustrated Barrichello, 36, clearly suspected that the switching of race-strategies penalised him while favouring his championship-leading teammate, Jenson Button.

"If I get the slightest sniff that the team are favouring Jenson, I'll hang up my helmet tomorrow," he declared to the American broadcaster Speed TV.

"I need to find out what happened. I'm sure everything is ok," he added.

Team bosses Nick Fry, and Brawn himself, denied that Button is being favoured.

"Nope, no. Absolutely not," Brawn, who was involved in the infamous team orders scandal involving Barrichello at Austria in 2002, said after Sunday's race.

"I hope Rubens doesn't think that, because we are not (favouring Button).

"I think you saw at the first corner that there are no team orders," said the Briton, referring to how Barrichello had been free to challenge Button for the lead of the race.