Marco Simoncelli has died after a horrific crash at the Malaysian MotoGP in Sepang.
The race was cancelled after four minutes when Honda rider Simoncelli fell and was hit by Colin Edwards and Valentino Rossi as he slid across the track.
The 24-year-old had his helmet knocked off in the accident and the race was immediately red-flagged.
Honda rider Simoncelli first entered MotoGP for the 2010 season.
He won his first pole position at the Catalunya race in June this year.
The accident happened at Turn 11 when Simoncelli's bike veered across the track into the path of Edwards and Rossi.
Simoncelli, who was motionless on the track after the impact, had been fourth at the end of lap one after qualifying in fifth.
Edwards also fell but escaped serious injury, while Rossi, on a Ducati, was able to return to the pits.
World champion Casey Stoner said: "As soon as I saw the footage it just makes you sick inside. Whenever the helmet comes off that's not a good sign."
Simoncelli's first podium finish came in the Czech Republic in August when he finished third but he bettered that with a second-place finish at the Australian GP.
The Italian started in the 125cc class in 2002 and moved up to the 250cc class in 2006.
He claimed the 250cc world title in 2008.
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http://news.bbc.co.uk/sport2/hi/motogp/15420069.stm)
Rest in peace Sic.