Cheltenham double for Nina Carberry Knock House (9/2 joint-favourite) defied top weight to give Carberry a double in the Cheltenham Club Amateur Riders' Handicap Chase. Mick Channon's charge jumped into the lead at the last and though long-time leader Foxbridge rallied on the run-in, Knock House would not be denied. The winning margin was down to a neck at the line, with Alternatif five lengths back in third. Channon said: "Nina gave him a great ride and Hen (Henrietta Knight, former trainer) has done all the schooling. "He's always been a nice little horse and Tim (Radford, owner) wanted to come to Cheltenham because he's got a box in the new stand, so it's great to find him a winner. "Three-mile-one is about as far as he wants to go at the moment. "We were worried about the trip up the hill here."