Brian Harding was hit with a 10-day ban after the stewards at Catterick ruled he had failed to ride out Guerilla for second place.
The Richard Guest-trained seven-year-old, sent off at 6-1 for the Turftv.co.uk Handicap Chase, had been beaten off by winner Stormy Beech before being nailed on the line for second by Whatcanyasay.
With eight runners taking part, each-way punters will still have collected but the local officials believe Harding was at fault and handed him the lengthy suspension.
He will sit out seven days action between December 16-22 and complete the ban between 26-28 of the same month.