Rossi came into Assen having lost the last two rounds to MotoGP World Championship leader Casey Stoner, pushing the Australian 26 points clear in the title chase, while Rossi was dealt a further blow when qualifying rain left him just eleventh on the grid - nine places behind Stoner's Ducati.

But Saturday dawned dry and with Rossi's hopes further boosted by a comfortable third in the warm-up, in which Stoner fell. Nevertheless, the Australian showed little signs of weakness as he stormed into an early lead, while Rossi made slow progress.

The Yamaha superstar, riding in a special Fiat 500 livery, made up little ground at the start but after the first couple of laps he found his rhythm and began a spectacular charge to the front, passing rider after rider with a series of bold moves and eventually making his way up to second behind Stoner by lap 12 of 26.

The seven-time world champion was then faced with the task of closing a two second gap to the championship leader, but within just a few laps he had done just that and moved to within striking distance of the lead. It was no easy job to pass the Australian however and he made several unsuccessful attempts before finally making a pass stick through the chicane with four laps remaining, eventually crossing the line 1.909 seconds clear.

"This was an incredible race. I think maybe one of the top five of my career!" smiled a delighted, and somewhat relived, Rossi. "Clearly starting from 11th is quite lucky for us because I've won a few times from that position, including last year at Sachsenring.

"Last night I didn't sleep so well and I couldn't have imagined that the race could turn out like this, in fact I was really a little bit worried after the qualifying and didn't know what to expect today! Once I got going though I saw that I had a great pace and so I just rode as hard as I could to get past everyone because I knew then that I could come back to Casey.

"When I finally got there I was quite tired, as were my tyres, plus he was riding very well and it was hard to overtake him, but my M1 worked brilliantly today and in the last few laps I was able to go past and win. I have to say a big thank you to Michelin and to my team, because today our package was brilliant and I was able to ride at the maximum.

"I'm so happy to win here in Assen, it's a special place for me and this is a great emotion! It was nice to have a special livery here as well, in the past I haven't been so lucky with new liveries but hopefully today has turned that around! Congratulations to Yamaha for 150 wins, I am glad that we could celebrate like this!" concluded Rossi, who will now start the second half of the 18 round season 21 points behind Stoner.

"This was a fantastic race with which to celebrate Yamaha's 150th win and we couldn't have dreamed of a better race than this after yesterday's qualifying," admitted team director Davide Brivio. "Valentino was incredible once again and he rode a truly amazing race. It was a great emotion for everyone to watch Valentino ride like this today. It's going to be a hard fight for the rest of year but we have a lot of motivation."

Of the first nine rounds of the championship so far, Stoner has won five, Rossi three and Chris Vermeulen one. However, despite Stoner's win advantage, the two title rivals have scored exactly the same points from the last four rounds - each taking two wins, a second place and a fourth.