This Day in Golf History: April 21

April has been a popular time of the year to hold the Senior PGA Championship, which is the oldest of the senior majors, starting in 1937. Stewart Cink just won this year’s playing by six shots on Sunday. On this date in 1991, Jack Nicklaus won his lone Senior PGA, at PGA National in Florida, with a 17-under 271 score, also a winner by six shots, ahead of Australia’s Bruce Crampton.