Rossi wins Sepang after Capirossi showdown.

A relentless race long battle between Valentino Rossi and Loris Capirossi went down to the final turn of Sunday's Malaysian Grand Prix at Sepang - as the reigning MotoGP World Champion took another chunk out of Nicky Hayden's points lead.

Rossi, who started from pole at the front of a 'unique' grid decided by free practice times after the cancellation of qualifying due to standing water, lost out to Capirossi and the injured Dani Pedrosa into turn one - but barged past them both to lead in the space of two corners.

Capirossi, the pre-event favourite, responded by outbraking his way back past the Yamaha rider into the final hairpin at the end of lap two - but couldn't break away from Rossi, and resorted to letting the Italian back past on lap 7 of 21.

The decision looked to have backfired when the amazing Pedrosa, riding with four stitches bridging a gaping wound in his knee, used the opportunity to pounce for second position, but Capirossi regrouped and repassed the 20-year-old Spaniard to be back within 0.3secs of Rossi's rear wheel as the halfway mark arrived.

Pedrosa, who could barely walk, gradually lost touch with the leaders in the second half of the race, leaving a fascinating Rossi vs. Capirossi duel. The Italians played cat and mouse with each other, each refusing to fully reveal their hand, until Capirossi launched a determined attack to retake the lead on lap 17.

The #65, winner last time out at Brno and last year at Sepang, then attempted to break the reigning champion - but Rossi and his Michelins were able to reel Capirossi and his Bridgestones back in on the exit of the tighter corners, then regain the lead with a premeditated move on lap 19.

This time it was Rossi who attempted to make a break, but Capirossi responded and the pair rode side-by-side along the home straight to start the penultimate lap, with Loris shouldering his way ahead through the right-left first chicane. Rossi hit back later on, but ran wide on the exit and allowed Capirossi to squeeze in front - then The Doctor made what looked to be a potentially race losing mistake with an off-line entry into the final hairpin.

That gave Capirossi a 0.6secs advantage as the last lap began, but Rossi charged hard and again made ground through the middle of the lap - and was ready to strike. The #46 jumped for the inside, nudging Capirossi off line in the process, to lead with just a long straight and the final hairpin to go.

Realising that Capirossi's potent Desmosedici could gain ground on the straight, Rossi took an ultra-defensive line heading into the final hairpin - but out-braked himself and slid sideways past the apex. That should have given Capirossi the opening he was looking for, but the double 2006 race winner also out-braked himself in his desperation to win - and ran even further wide.

Rossi thus held his lead on the exit and went on to win by 0.8secs, with Pedrosa producing arguably the ride of the race to finish just 3secs further back in third. But the shock podium was not without consequences for the Repsol Honda rider and he was forced to seek medical treatment immediately after the podium.

Meanwhile, Rossi celebrated his fifth victory of the season by taking a chair onto the podium and relaxing on it - to illustrate how exhausting the victory battle had been - and soon found Capirossi on his lap!

Championship leader Hayden ran fourth for the entire race - meaning his points lead over Pedrosa has been cut from 25 to 22 points, while Rossi has closed the gap from 38 to 26 with four races and 100 points still up for grabs, starting next weekend in Phillip Island.

Behind Hayden, Sete Gibernau took a safe fifth on his comeback ride, while Suzuki's John Hopkins recovered from a poor start that left him just eleventh at the end of lap one to claim sixth ahead of Roberts, Stoner, Melandri and Edwards.

Malaysian Grand Prix:

1. Rossi
2. Capirossi
3. Pedrosa
4. Hayden
5. Gibernau
6. Hopkins
7. Roberts
8. Stoner
9. Melandri
10. Edwards
11. Vermeulen
12. Checa
13. de Puniet
14. Tamada
15. Hofmann
16. Ellison
17. Cardoso