A five-week suspension threatens Glyn Schofield's bid for two Group One wins in Melbourne.

Schofield was banned for five weeks after he was found guilty of not riding Springbok Flyer out the winning post at Warwick Farm on Wednesday.

Springbok Flyer led until the closing stages before the stayer was beaten in a photo-finish.

Stewards said Schofield stopped riding Springbok Flyer two strides before the post, an action they found was prejudicial to his mount's chances.

Schofield's ban will start after he rides at Randwick on Saturday and ends on February 28.

He is likely to appeal the ban to have it overturned or reduced, allowing him to continue a successful association with Group One star Boban and highly rated two-year-old Extreme Choice.

Boban and Schofield are scheduled to chase a sixth Group One win together in the C F Orr Stakes on February and the jockey also has the inside running to ride Extreme Choice in the Blue Diamond Stakes.

Schofield rode the Mick Price-trained Extreme Choice to an impressive win in a sales-restricted race at Randwick last month.

The Blue Diamond Stakes is at Caulfield on February 27.