[2] He also played for the Los Angeles Dodgers, Houston Astros, Detroit Tigers and the Boston Red Sox.

[3] He believes that he is a distant cousin of Baseball Hall of Fame member Christy Mathewson although, the exact relationship is not known.

On November 29, 1971, Billingham was acquired from the Astros along with Ed Armbrister, Cesar Geronimo, Denis Menke and Joe Morgan.

Billingham was removed from the game in favor of reliever Clay Carroll by Reds' manager Sparky Anderson while facing the first Oakland batter in the bottom of the ninth inning.

[6] In the 1975 World Series, he was the starting pitcher for Cincinnati in their Game 2 victory where, Billingham gave up a first-inning run before holding the Boston Red Sox scoreless for the next four innings.

[7] His scoreless streak continued in Game 6 where he appeared as a relief pitcher and allowed one hit in one inning pitched.

[1][10] In a 13-season major league career, Billingham posted a 145–113 record with 1,141 strikeouts and a 3.83 earned run average in 2,231.1 innings pitched, including 27 shutouts and 74 complete games.