Jorge Lorenzo ended title rival Casey Stoner's run of three straight victories with an emphatic display in the San Marino Grand Prix.
The Spaniard's third win of the season was made all the sweeter as Stoner lost second place to his Honda teammate Dani Pedrosa six laps from the end, allowing Lorenzo to close to within 35 points of the championship lead.
"It's fantastic," Lorenzo enthused. To be back with a very good bike is great. I want to thank all the team for this."
The race had initially looked like being the three-horse fight widely predicted, as Stoner and Pedrosa trailed Lorenzo's Yamaha away the start – the Spaniard stealing the lead on the first run down to Turn 1.
Behind them Ducati's Valentino Rossi gave a partisan home crowd reasons to be optimistic with a storming opening which saw him rise from 11th on the grid to fifth by lap two.
Rossi's pace faded slightly and he eventually lost contact with the battle for fourth, contested by Gresini's Marco Simoncelli, Honda's Andrea Dovizioso and Yamaha's Ben Spies.
A similar fate befell Stoner. Having shadowed Lorenzo intensely for the first 12 laps, his pace began to slip away, allowing the Spaniard – who set a new lap-record at the midway stage – to start rapidly building a gap.
Stoner then fell back into the clutches of Pedrosa, who passed him for second with a bold move into Curvone on lap 22. Stoner finished a comfortable third, leaving him 35 points ahead of Lorenzo heading into the final five rounds.
Behind them, Simoncelli had built a small gap in fourth but saw it eroded in the final laps, culminating in a dramatic three-way scrap on the final lap.
Dovizioso twice passed Simoncelli only to see his fellow Italian fight-back and eventually claim fourth by just 0.037sec on the line.
Spies brought the Yamaha home in sixth ahead of Rossi, who ended in a relatively lonely seventh for Ducati. His teammate Nicky Hayden had earlier dropped his bike at Turn 15 and retired from the race.
Tech 3's Colin Edwards had lain eighth but dropped rapidly as his pace tailed off in the closing stages, coming home 13th at the flag.
Eighth instead went to Suzuki rider Alvaro Bautista, with Hector Barbera and Cal Crutchlow rounding out the top ten.
Results – 28 laps
Pos Rider Team/Bike Time/Gap
1. Jorge Lorenzo Yamaha 44m11.877s
2. Dani Pedrosa Honda + 7.299s
3. Casey Stoner Honda + 11.967s
4. Marco Simoncelli Gresini Honda + 17.353s
5. Andrea Dovizioso Honda + 17.390s
6. Ben Spies Yamaha + 18.092s
7. Valentino Rossi Ducati + 23.703s
8. Alvaro Bautista Suzuki + 30.678s
9. Hector Barbera Aspar Ducati + 37.502s
10. Cal Crutchlow Tech 3 Yamaha + 37.720s
11. Hiroshi Aoyama Gresini Honda + 39.548s
12. Karel Abraham Cardion Ducati + 40.506s
13. Colin Edwards Tech 3 Yamaha + 53.349s
14. Randy de Puniet Pramac Ducati + 1m02.366s
15. Toni Elias LCR Honda + 1m20.156s
Loris Capirossi Pramac Ducati 9 laps
Nicky Hayden Ducati 2 laps