William Glenn McCahan (June 7, 1921 – July 3, 1986) was an American professional baseball player and right-handed pitcher in the Major Leagues with the Philadelphia Athletics from 1946 to 1949.

He graduated from Duke University and served in the United States Army Air Forces during World War II, attaining the rank of second lieutenant and earning his pilot's wings.

[2] In his final start of the year, on September 29 at Shibe Park, McCahan went seven innings against the New York Yankees and allowed only two runs (both earned), but the game was ended prematurely with the Athletics trailing 2–1 by a city curfew that prohibited night baseball on Sundays in Philadelphia.

With one out in the second inning, Athletics' first baseman Ferris Fain, after fielding a routine ground ball, threw wildly to McCahan, covering first base.

However, while he was working for an oil company during the 1947–1948 offseason, McCahan injured his shoulder lifting barrels[5]—ruining his 1948 season and his long-term MLB career.