It was the race MotoGP fans have been waiting for, but certainly hadn't expected, at Laguna Seca on Sunday - when Valentino Rossi overcame a practice deficit to battle furiously with reigning world champion Casey Stoner at the US Grand Prix.

Stoner, winner of the past three rounds, held a commanding half-second advantage over the field throughout practice and qualifying, leaving Rossi to joke about needing a 30-second head start to prevent the reigning world champion taking his fourth victory in a row on Sunday.

But some pre-race modifications extracted vital tenths out of Rossi's YZR-M1 and he combined his new found pace with a clear strategy of counter-attacking whenever the Australian took the lead.

That determination to 'smother' Stoner's advantage resulted in some thrilling overtaking: Stoner twice lost the lead to Rossi at the top of the Corkscrew - Valentino running over the dirt to make the second pass stick, forcing them both wide - and Stoner was twice block-passed by the Italian under braking for Turn Five.

Rossi also put up a stubborn defence. Stoner, who had closed to within 20 points of Rossi heading into the event, was stronger along the curved home straight - something Rossi reacted to by covering the inside, forcing Stoner to ride the long way around.

Stoner still made several such brave moves stick, but - just as Rossi had surely been hoping - began to show signs of frustration when he ran wide into the double apex second turn just moments after squeezing past the #46 on lap 14.

It took Stoner less than two laps to bridge the half second lead the mistake had handed Rossi - but his next error had more serious consequences. On lap 24 of 32 Stoner's rear wheel bobbled as he braked hard for the tight final turn, forcing the Desmosedici rider to run off track - where his front wheel dug into some soft gravel, tipping him over.

That mistake handed Rossi his first victory since June Italian's Grand Prix by 13 seconds from Stoner, who in turn finished 13 seconds in front of third placed Chris Vermeulen, riding in what seemed like a different race.

In terms of fastest laps, Stoner's best was 0.225secs quicker than Rossi - but third fastest Vermeulen was over one second slower than Stoner!

It had been a truly epic display of racing talent, but when Rossi attempted to shake hands with Stoner in parc ferme immediately afterwards, an angry Stoner refused.

A smiling Rossi responded by patting Stoner on the back and saying "this is racing Casey."

"Oh this is racing?" replied Stoner. "Okay, we'll see..."

There hasn't been such parc ferme tension since Rossi and Sete Gibernau collided at the final turn of the 2005 Spanish Grand Prix - even the presence of Tom Cruise did little to lighten Stoner's mood - but it should be remembered that Stoner was speaking in the heat of the moment and whilst still coming to terms with losing a race he looked certain to dominate.

Stoner and Rossi appeared on more amicable terms by the time the podium ceremony took place, although Stoner later stood by his claim that some of Rossi's moves were 'aggressive' - while taking full responsibility for the accident that ultimately cost him a chance of victory.

"We [Rossi and Stoner] were side by side much of the race," said Stoner. "There were a couple of moves I wasn't very happy with. Valentino was riding a great race and was very defensive and hard to pass. He wasn't making any mistakes. I was basically trying to find the right place to get past.

"I thought the passing was a little rough. I've done a lot of overtaking moves, and there were a couple of passes which were some of the most aggressive I've seen in a long time," he explained. "Just a couple I wasn't happy with. The others were fine - clean side by side.

"I made a mistake going into the last corner and I hit a big patch of sand instead of dirt and just lost the front of the bike when I was trying to get back on track," confirmed Casey. "I have to deal with it."

Ducati MotoGP Project Leader Livio Suppo backed his riders comments, calling some of Rossi's moves 'over the limit' whilst highlighting the exceptional talents of Rossi, Stoner and the absent Dani Pedrosa.

"It was a very tight race, spectacular to watch and evidence that it is not only the electronics that make the difference in this sport, but two riders who are one step above everybody else at the moment," he said. "Dani is also a part of that small club but unfortunately he wasn't here today.

"After three straight victories for Casey, today was Valentino's turn, that's fair enough. For sure if Casey had not shown a tremendous coolness and maturity, there would have been at least a few occasions in which they both could have crashed as a result of manoeuvres which, in our opinion, were a bit over the limit on Vale's part," he declared.

Rossi responded to the criticism by saying: "I need the tactics I need to win, and for sure, we make it hard for overtaking... I am sorry that Casey thinks some of [the passes] were a bit strong but I really don't agree; I passed only on the brakes, I braked in the same places every time [some had suggested Rossi brake-checked Stoner] and we never touched. Of course this was an aggressive race, but it was definitely a fair one... I enjoyed the battle, anyway."

Valentino, the master mind games, is unlikely to lose sleep over disapproving words from either Stoner or Suppo and was soon reliving 'a hell of a battle'.

"For me this race is fantastic," he said. "It is my first victory in Laguna Seca. We made some modifications to our bike after warm-up and these gave us the last few tenths that enabled me to fight with Casey today.

"I got a good start and I was able to pass him in the first lap, but I knew I had to try and stay in front of him and it was impossible to relax even for one second. My M1 was brilliant and so were my Bridgestone tyres; I really only made one mistake, at the corkscrew when I went a bit wide but in fact the dirt had quite good grip also!

"Casey was a bit faster on the straight than me but I was stronger on the brakes so I had to make all my passes there. I don't know how many times we changed the lead but it was a lot and it was great, great racing for me and I think also for the fans, because it's been a while since we've been like this.

"It was a hell of a battle, a lot of fun and it is an important victory," smiled the seven time world champion.

Rossi also explained why he stopped at the top of the Corkscrew to kiss the ground during his slowdown lap. "The Corkscrew is difficult [for me] in 2005 and 2006. I practiced and practiced to make it right," he said.

"Although it was not there, we saw the 'heart' on Valentino's helmet again today!" said team manager Davide Brivio. "This is a great victory because throughout the entire weekend we were at a disadvantage, but nobody ever gave up and we worked until the very last minute to find a way to help Valentino to fight with Casey.

"We tried to optimize everything we had and at the end 'The Doctor' completed the operation! This was a race Valentino did not want to lose. This is Valentino, one who never gives up and fights until the end. I hope to see battles like this one until the end of the championship," he added.

Rossi is now looking forward to enjoying a much needed holiday - but expects Yamaha to use the time off until Brno on August 17 to work flat out on improvements to keep his M1 at the top of the world championship standings.

"We have to work, to fix some of our problems, because it is a race to the end and the battle will be very hard. I have 25 points, which is a good advantage, but it's not amazing," he warned. "But anyway it was a good outcome. We have to work to try to go fast because last year was a disaster for us. There were a lot of problems. Today I have more points now than I had in all of last year, and I still have seven races to go. I'm strong and I'm ready for the battle."

Stoner meanwhile was quick to put the outcome of the US Grand Prix into perspective.

"We lost five points today," he said. "The important thing is that we've come away from here with 20 valuable points and after being written off in some quarters four races ago we now go on our summer holiday with a fighting chance of winning the title again. We're 25 points behind, which is a big gap, but there are seven races left and a lot can happen. We can take a lot of positives out of this weekend."