Mark Catcavecchia, 1991 Ryder Cup at KiaWah Island (Golf)

Calcavecchia was four up with four holes to play in his singles match against Colin Montgomerie. He lost the 15th and 16th, and then, at the par-3 17th, after Montgomerie hit his tee shot into the water and all he had to do was put his ball somewhere on dry land, Calcavecchia topped his tee ball into the water. He then missed a 2-foot putt, which would still have given him the win. All told, he made two triples and two bogies to lose the final four holes and halve (tie) the match, when a win would have clinched a victory for the United States. Fortunately for Calcavecchia’s subsequent mental health, the United States won the Ryder Cup anyway.