John William Leister (born January 3, 1961) is a former starting pitcher in Major League Baseball who played for the Boston Red Sox.

Signed as a free agent in 1984 he was originally drafted by the New York Mets out of high school in Great Falls, Montana.

Instead Leister tried out as quarterback for the Pittsburgh Steelers,[1][2] who later cut him at the end of training camp, opting to keep Terry Bradshaw, who had undergone an off-season elbow surgery, for his final season.

Leister also was drafted and was briefly a member of the Michigan Panthers of the United States Football League (USFL), but left the team to play professional baseball with the Red Sox.

In a two-season major league career, Leister posted a 0-2 record with 19 strikeouts and an 8.50 earned run average in 36.0 innings of work.