bumper
n.— «Collier Hill’s first start was in a National Hunt Flat race—more commonly known as a “bumper”—designed for horses deemed too slow to win on the Flat en route to a career over jumps.» —“Bargain Buy Collier Hill Can Strike in HK Vase” Virtual FormGuide (Australia) July 12, 2006. (source: Double-Tongued Dictionary)