Preview - Malaysian Grand Prix.

After the shock of last Sunday's Japanese GP collision with countryman Marco Melandri, which cost Valentino Rossi his first chance to wrap-up the 2005 world title, the Yamaha star will be forced to wait just seven days before getting his second opportunity at this Sunday's Malaysian Grand Prix.

Fourth place or above in Sepang will now bring Rossi his fifth consecutive premier-class crown and seventh ever world title - and the Italian arrives at Sepang full of confidence and showing no ill effects from his Motegi exit.

However, Melandri - the innocent victim of Rossi's misjudgement - was not so lucky and could well miss the race after having 30 stitches inserted in a deep wound on his right ankle caused by the footrest of his machine when he fell.

By contrast, Rossi's pre-race confidence is substantiated by his results round the 3.447 mile Sepang circuit which is situated near Kuala Lumpur International airport, 30 miles south east of Malaysia's capital city.

The Doctor has won three times out of the last four years as he chases his tenth victory of the season in the 21 lap race on Sunday. Last year he won the race from Max Biaggi and also established new pole and race lap records.

Biaggi, also a former Sepang MotoGP winner, is now the only man with an outside chance of stopping Rossi, but the Repsol Honda rider must score 13-points more than his compatriot to maintain those hopes beyond this weekend.

Nevertheless, Biaggi's chances of taking the runner-up spot for the fourth time in his premier-class career are much more favourable, having broken 16-points clear of Colin Edwards after his second podium in a row at Motegi last time out.

American Edwards has finished every race this season, including three podium finishes, and his sixth place in Motegi pushed Rossi's Yamaha team-mate into third place for the first time.

However, Edwards could only manage eleventh place for Honda at Sepang last season and has not visited the podium since he took second place in his home race at Laguna Seca.

Meanwhile, there are a number of riders looking to continue their impressive Japanese form this weekend - not least race winner Loris Capirossi, who brought Ducati their first MotoGP victory since 2003 and will be out to prove he, his team and Bridgestone tyres can run consistently at the front.

Capirossi's team-mate Carlos Checa is fighting for his MotoGP future and rode brilliantly to finish fourth in Motegi, just one place in front of the Suzuki of American John Hopkins who produced his best ever MotoGP result, after signing a new two year contract with the team.

Kenny Roberts, Hopkins's team-mate, returns to Sepang where he brought Suzuki 500cc success in 1999 and 2000. The former World Champion finished eighth in Japan and will be looking for a good result with his future with the team very uncertain.

Nicky Hayden, Biaggi's Repsol Honda team-mate, was a disappointing seventh in Motegi and will be looking for an improvement while Honda men Sete Gibernau and Alex Barros will be hoping to forget their Motegi crashes.

Kawasaki's Alex Hofmann was another Motegi faller and broke his heal. He will miss the race on Sunday and looks certain to be replaced by former 250cc World Champion, Frenchman Olivier Jacque.

But another subsititue rider will cause even greater interest since - with Troy Bayliss missing his second successive race due to a wrist injury, sustained in a motocross training accident in Australia - Shane Byrne will get his dream chance of a competitive MotoGP ride on the former World Superbike Champion's Camel Honda.

The former British Superbike Champion has not ridden since his home round at Donington Park after a split between Proton Team KR and engine suppliers KTM but he will have a major chance to impress over the next two weekends, having also been pencilled in to replace Bayliss at the following event in Qatar.

Thereafter, if the rumours are correct, Ten Kate Honda World Superbike star Chris Vermeulen could take the ride, alongside Alex Barros, for the final three races - should Bayliss be unfit to return.

In the 250cc class, Spanish teenager Dani Pedrosa will be out to repeat his victory of last year to push him nearer retaining his title before moving to MotoGP next year.

The Spaniard finished a brave second in Motegi behind his Movistar Honda team-mate Hiroshi Aoyama, despite crashing three times in practice and qualifying.

Pedrosa leads Australian Casey Stoner by 63 points with the 125cc World Champion Andrea Dovizioso in third place. Stoner finished third on the Aprilia in Motegi and won the 125cc race for KTM at Sepang last year.

Jorge Lorenzo will not be taking part this weekend after being suspended for his part in a collision with Alex de Angelis on the final lap in Japan.

The 125cc Championship leader Thomas Luthi faces a battle for fitness before the vital race on Sunday. He dislocated his shoulder and damaged his ankle in the horrendous start line accident at Motegi that brought a premature end to the race.

Luthi leads Finnish KTM rider Mika Kallio by just three points while the chasing pack of Gabor Talmacsi and Marco Simoncelli dropped back after crashing.