Marvin Mardo Goodwin (January 16, 1891 – October 21, 1925) was a professional baseball player who was a pitcher in Major League Baseball from 1916 to 1925. He would play for the Washington Senators, St. Louis Cardinals and Cincinnati Reds. Goodwin was known for throwing the spitball, and he was one of the 17 pitchers allowed to continue throwing the pitch after it was outlawed in 1920. Goodwin was a pilot in World War I, and died after the war from injuries sustained in a training flight while a member of the Army Air Service Reserve. He is believed to have been the first professional athlete killed as a result of a plane crash.