John Hopkins will miss Saturday's Dutch TT at Assen due to lower leg injuries sustained in a huge Friday qualifying fall.

The Anglo-American, who also fell early in the hour-long session, lost the front of his Ninja ZX-RR under braking for the left-hander at turn 12, one of the fastest corners on the Assen circuit, in the closing minutes of the timed session.

After falling, the #21 managed to separate himself from his sliding machine, but appeared to lose little speed as he skimmed across the gravel and sustained the injuries to his left leg when he collided with the tyre wall on the outside of the corner.

The initial assessment in the Clinica Mobile was that Hopkins sustained a fractured left ankle and suspected compression injuries to his left knee and will be out of action for at least 20 days - but the 25-year-old will return to Los Angeles tomorrow for a further medical examination by Doctor Art Ting.

Only once full extent of his injuries are known will a decision be made as to whether Hopkins will return to action at the next race in Sachsenring, which takes place in just two weeks time.

"John's crash may affect the next two races, which is a real disappointment," stated Kawasaki competition manager Michael Bartholemy. "The injuries to his ankle were not caused by the fall itself, but the collision with the unprotected wall on the outside of turn 12. John will now return to America for treatment and we'll make a decision on Sachsenring once we know the extent of his injuries."

If Germany isn't possible, Hopper will be aiming to return to action at his home US Grand Prix, to be held at Laguna Seca on July 20.

Team-mate Anthony West will line-up 17th on the Dutch TT grid.