Billy Casper, 1968 Bob Hope Desert Classic (Golf)

Casper was two shots off the lead in the final round when he came to the par-3 4th hole. Just as he reached the top of his backswing, a spectator slipped on the rocky hill above him, causing a landslide that startled Casper into a cold shank. The resulting double-bogey 5 dashed his chance to win the tournament.