Hector Barbera denied Jules Cluzel a shock victory in a thrilling 250cc series opener at Losail.
The result gave Sito Pons's new Pepe World WRB 250cc team a debut victory, and was the ideal way for Barbera to announce his return after missing the final few races of 2008 with spinal injuries following a Motegi practice crash.
125cc champion Mike di Meglio completed the podium in his first 250cc race, taking the place from surprise star performer and fellow rookie Raffaele de Rosa on the last lap of the shortened 13-lap event.
Pole-sitter and title favourite Alvaro Bautista only managed seventh place after a variety of incidents.
The race began 40 minutes behind schedule and on a treacherous track thanks to the downpour that had truncated the 125cc race.
A chaotic first corner saw Barbera charge into the lead from fourth, while his front row partners Bautista, di Meglio and Hiroshi Aoyama tumbled down the order - Bautista being barged right back to 11th.
2008 Losail winner Mattia Pasini fared even worse, tangling with Lukas Pesek at Turn 1 and retiring.
Barbera swapped the lead with veteran Alex Debon at first, while Cluzel made rapid progress from 13th on the grid.
An error by Debon on lap three allowed Barbera to reclaim first place, with Cluzel following him through. A lap later, Cluzel - who had never finished above 10th in a 250cc race and who dropped back to 125cc without success last year - stunned his rivals by slicing past Barbera to take the race lead.
This duo then edged away from the frantic pack behind. Cluzel appeared comfortable up front, but Barbera never let him get more than one second ahead.
With three laps to go, the fairytale ended as Barbera drafted Cluzel down the pits straight and outbraked him into Turn 1, going on to win his second 250cc race by 0.8 seconds.
Di Meglio charged through to third, with Aoyama pushing de Rosa back to fifth after the Italian had run third for many laps.
Bautista languished outside the top ten early on, then started setting fastest laps and carving through the field once he had acclimatised to the conditions. He got as high as fourth place, only for some small late errors to see him pushed back to seventh again, behind Thomas Luthi, and ahead of Ratthapark Wilairot, who had enjoyed his best race yet to battle for the podium for much of the distance.
Reigning champion Marco Simoncelli did not take part, having withdrawn after practice due to wrist injuries sustained in a motorcross accident last week.
Pos Rider Bike Time 1. Hector Barbera Aprilia 26m50.940s 2. Jules Cluzel Aprilia + 0.826s 3. Mike di Meglio Aprilia + 6.181s 4. Hiroshi Aoyama Honda + 6.609s 5. Raffaele de Rosa Honda + 6.656s 6. Thomas Luthi Aprilia + 6.672s 7. Alvaro Bautista Aprilia + 7.608s 8. Ratthapark Wilairot Honda + 8.349s 9. Roberto Locatelli Gilera + 15.032s 10. Gabor Talmacsi Aprilia + 20.348s 11. Hector Faubel Honda + 20.465s 12. Shoya Tomizawa Honda + 28.402s 13. Lukas Pesek Aprilia + 28.906s 14. Alex Debon Aprilia + 33.779s 15. Alex Baldolini Aprilia + 36.988s 16. Bastien Chesaux Honda +1m01.730s 17. Imre Toth Aprilia +1m03.512s 18. Vladimir Leonov Aprilia +1m32.385s 19. Aitor Rodriguez Aprilia +1m38.752s Retirements: Rider Bike Laps Karel Abraham Aprilia 8 Axel Pons Aprilia 0 Mattia Pasini Aprilia 0