Silicone Racing's Dean Harrison may be forced to sit out Monday's Superbike Classic TT after a crash in practice this evening.

The Bradford rider slipped off his Laylaw Yamaha Lightweight bike and has sustained rib injuries. Harrison was taken Nobles Hospital and his team have said he will remain there overnight.

Harrison had posted the fastest time of the week on his Silicone Engineering Kawasaski Classic TT Superbike (124.562mph) while Michael Dunlop completed his first lap on the Team Classic Suzuki with 119.89mph in the afternoon which he improved with a 123.28mph standing start lap in the evening session.

But it looks like their much-anticipated head-to-head may not happen.