Thursday afternoon practice for the Assen MotoGP round has been canceled due to poor track conditions in the wake of an oil spillage in an earlier Moto2 session.

An engine failure on Alex Baldolini's Moto2 bike coated much of the already-damp track with oil, and it proved impossible to clear the surface sufficiently and still allow enough time to run all the world championship practice sessions.

The 125cc practice session was postponed initially, with MotoGP practice delayed, before eventually the decision was made to cancel the afternoon's planned action completely.

Friday morning's practice sessions are likely to be extended to make up for some of the track time lost. With practice one having been rain affected, teams currently face the prospect of going into qualifying extremely short of dry running.