Alvaro Bautista has become the first double winner of the 2009 250cc season, with home victory at round six in Catalunya - a race that saw reigning world champion Marco Simoncelli crash out.
Tensions had been running high before the race following Simoncelli and Bautista's clash last time out at Mugello, which ended with Simoncelli being given a suspended ban.
That decision left Simoncelli furious at what he felt were double standards while Bautista's camp were unhappy that the Italian was allowed to keep his place ahead of the Spaniard in the race results.
Against that backdrop, and with the Spanish crowd booing Simoncelli at every opportunity, the race began with pole sitter Hector Barbera holding his advantage into turn one - but with Bautista and Simoncelli first and second by lap 3 of 23.
Moments after taking second, Simoncelli lost the front of his Metis Gilera through the left hander at the end of the back straight and slid into the gravel - prompting deafening applause and jeers from the partisan fans. The Italian rejoined 25th and last, then retired several laps later. Simoncelli has now failed to score in three of the six rounds.
With his arch-rival out, world championship leader Bautista edged slightly away from Barbera with every passing lap to hold a 2.4sec advantage over the Pepe World Aprilia rider and Mugello winner Mattia Pasini by the midway point.
Bautista, winner of round two at Motegi, went on to claim his first win in Spain since joining the 250cc class in 2007 by 7.185sec, extending his title lead to 12 points in the process.
Second place went to Bautista's nearest title rival Hiroshi Aoyama, who seemed to overcome some kind of technical problem before charging spectacularly forwards in the closing stages.
The Scot Honda rider snatched third from Pasini with three laps to go, then levered Barbera out of second at the end of the back straight on the very last lap.
Simoncelli has now dropped 47 points behind Bautista.
Race results - Catalunya:
1. Bautista (Aprilia)
2. Aoyama (Honda) +7.185sec
3. Barbera (Aprilia) +7.282sec
4. Pasini (Aprilia) +10.784sec
5. Debon (Aprilia) +15.740sec
6. Luthi (Aprilia) +15.780sec
7. Wilairot (Honda) +28.654sec
8. Abraham (Aprilia) +31.600sec
9. de Rosa (Honda) +33.760sec
10. Faubel (Honda) +33.843sec
21. Markham (Honda) +1 lap