Robert Thomas Kaiser (born April 29, 1950) is an American former Major League Baseball pitcher, a left-handed reliever who appeared in five games for the Cleveland Indians during the 1971 season.

In his MLB debut, he surrendered a home run to the first batter he faced, Duane Josephson of the Boston Red Sox.

But he finished the inning strongly by striking out a future Hall of Famer, Carl Yastrzemski.

[1] All told, he allowed eight hits and three earned runs in six MLB innings pitched, with three bases on balls and four strikeouts.

This biographical article relating to an American baseball pitcher born in the 1950s is a stub.