He tried hard to conceal his disappointment at the end of a race he knew had been taken away from him in Barcelona, but Rubens Barrichello's face revealed far more than his words at the end of the Spanish Grand Prix this weekend, as rumours intensify within the Formula 1 paddock that he is already the 'number two' driver at Brawn GP.

Having been pipped to pole position around the Circuit de Catalunya by team-mate Jenson Button - the legacy, he suggested, of having timed his final run too early - the veteran Brazilian immediately sought to make amends when the starting lights went out, storming past both Sebastian Vettel and the sister BGP 001 to grab the lead into turn one.

He would remain there all the way to his first pit visit on lap 19, having eked out a small margin over Button along the way, but unbeknown to him the team had switched the British star over to a two-stop strategy during the stops, whilst he had been left on three. That meant that whilst the 36-year-old now had an even greater lead, he would need to push harder still to extend his advantage in order to remain ahead at the end of the race, and ultimately it was just too tall an order to pull off.

At one point looking in danger of missing the podium altogether, Barrichello took the chequered flag 13 seconds behind Button in the runner-up position - his second rostrum appearance of the season, but one that was scant reward for what he felt should have been his first F1 victory in more than four years. Fastest lap to his credit was little consolation.

"The race began really well for me," the S?o Paulista related, "and I had a great start overtaking Sebastian and Jenson to be leading coming out of turn one and through the safety car period. The car was feeling really good during the first stint, and getting out from my first stop ahead of Nico [Rosberg] on-track set the race up nicely for me.

"I don't know why they changed Jenson's strategy, because we were both on three stops - for me it came as a surprise when they said he was changing to two. Before the race took place the agreement was that both cars would be doing three stops, so I wonder why they didn't change me to a two-stop as I was the one who was running longer.

"From then I knew that I had to go flat-out to make my strategy work. However, I suffered on my third set of tyres and was not able to set the lap times which would have kept me ahead of Jenson. With the pace that I had pulling away from him [early on], I really felt I had it in the bag, and then all of a sudden after my third stop I was on a tyre that wasn't working particularly well, and when I saw he was in front of me it was very disappointing.

"It was a great result for Jenson and the team today, and at the end of the day I've got to be very happy with myself. I'm going to leave the track with my head held high because I did the best I could; my set-up was great and the car was feeling good, but the strategy just didn't work. I have to keep on going flat-out as much as I can, because I believe I have the ability to win the championship. Right now everything is going in favour of Jenson, but I am a positive person and I just have to keep my side up. I am confident that my victory will come soon."

When asked whether he believed the ex-Honda F1 outfit was already throwing its weight behind Button's championship bid - with the 29-year-old now having triumphed in four of the opening five grands prix of the new campaign - Barrichello was enigmatic, not denying the suggestion but equally asserting that he hoped he would be given an equal chance to prove his credentials.

"I hope not," the nine-time grand prix-winner responded. "I've been in a team that was very much in favour of somebody else; Ross [Brawn] was there too, but I think he likes me very much and that's why I'm racing for this team. Again I have to put my hands to the sky and say thank you for the opportunity to be racing such a fantastic car. I have the ability to win races and today I must be happy with my performance. It is disappointing that I haven't won yet, but I have to keep on trying."

Team principal Brawn, for his part, pinned the blame for Barrichello's failure to win the grand prix firmly on his inexplicably poor pace on the softer-compound Bridgestone rubber in his third stint. Rubbishing speculation that the objective had always been for Button to emerge on top, the Englishman seemed to hint that the race had been Barrichello's to lose - and he had lost it.

"For us, three stops was always the quicker strategy," the 54-year-old underlined, "particularly with the 'prime' [tyres] being so poor. Rubens had a great start to be leading the race from lap one, and we asked both drivers to push as hard as possible to build a lead over the chasing pack. Rubens was going extremely quickly at the front at that time and his three-stop strategy was clearly the quickest option for him.

"What was strange and disappointing is that on his second set of 'options' he was quite slow - much slower than we anticipated - and probably half a second to a second off what he could or should have been doing. That was the crucial part that ultimately cost him the race, because up until then he was looking good on Jenson.

"We swapped Jenson around because putting him on a three-stopper would have put him right behind Rosberg and we were scared of getting held up, so we went for the two-stop with Jenson but three still looked good - it was just that the tyres didn't work. We were choosing a strategy for Rubens to win the race; he has performed extremely well throughout this weekend and it has been largely thanks to his input that we have been able to maximise our pace and achieve the successes of today.

"It's very early days in the championship - we're five races in with twelve to go, so there's a long way to go - and both of our drivers are racing each other, as you could see at the beginning. They've got freedom - the only rule is 'don't knock each other off'."