Ulsterman Jeremy McWilliams crashed out of the Brazilian MotoGP in Rio de Janeiro on Saturday.

McWilliams came off during the fifth lap when he was holding fourth place in rain-lashed conditions.

McWilliams was helped from the circuit holding his shoulder, but the injury is not thought to be too serious.

''The engine just appeared to seize on me and I just hit the deck,'' said a disappointed McWilliams.

''I have a plate in my shoulder, and I am going to go to hospital to have it X-rayed.

''I landed awkwardly on it. I don't think it is too bad.

''I am just so annoyed.''

McWilliams started on the front row of the grid after qualifying as third fastest.

The race was won by Valentino Rossi with Max Biaggi second and Kenny Roberts third.