Ian Hutchinson is in hospital with a compound fracture to his left leg after a first lap crash while racing at Silverstone.
He came off in wet conditions on the first corner of the British Supersport Championship race and was then hit by a following machine.
The Bingley Bullet, who made history by winning all five solo races at TT 2010, was treated by medics at the track before being air-lifted to hospital.
It was later confirmed he had suffered a compound fracture to the tibia and fibula in his lower left leg.
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