Hampshire motocross startlet Billy Mackenzie was taken to hospital with a dislocated shoulder and a broken nose after a heavy fall in Sunday's British Grand Prix at Wakes Colne in Essex.

The Yamaha Dixon rider crashed during qualification for the 125cc race and, although he wasn't detained in hospital, the young Scot from Titchfield was unable to take any further part in the Grand Prix.

Mackenzie's absence lost him second place in the championship to fellow Yamaha rider, the American Jeff Dement, who was the overall winner in Essex from series leader Stephen Sword.

The circuit at Halstead near Colchester had been heavily watered overnight, making heavy going for the 125s.

And Mackenzie, on the 250F four-stroke, was just starting a fast lap when his rear brake grounded out in a deep rut approaching the face of a jump.

He was sent cart-wheeling into the air before landing heavily and was lucky to escape even more serious injury.

Steve Dixon, manager of the Swanmore-based Yamaha team, said: "In think maybe the track had been overwatered in some areas and it was a bad fall.

"Billy will be seeing a specialist this week to see how bad the shoulder injury is but the hospital X-ray revealed no broken bones."

Yamaha new boy Mark Jones brought some consolation for the Meon Valley team by taking eighth place overall in the 250cc event.