Albert "Lefty" Gerheauser (June 24, 1917 – May 28, 1972) was an American professional baseball player who pitched in the Major Leagues for five seasons (1943-46 and 1948), for the Philadelphia Phillies, Pittsburgh Pirates and St. Louis Browns. He played in the minor leagues for eight seasons, mainly in the New York Yankees' system, before making the major leagues. As of 2024, he was the last player who made his major league debut on Opening Day as a starting pitcher.