Shellenback threw and batted right-handed and stood tall and weighed 200 pounds (91 kg). After attending the
University of Santa Clara, he became a
professional baseball player during World War I and was acquired by the
Chicago White Sox at age 19 during the 1918 season. In 36
American League games during 1918–19, Shellenback won ten games and lost 15, with an
earned run average of 3.06 in 217
innings pitched. He appeared in his last MLB game on July 5, 1919, before his contract was transferred to the
Minneapolis Millers of the
American Association. Although Shellenback posted a 7–3 record there, because of his minor league status, he was not included on a list of
"grandfathered" spitball hurlers who would be allowed to continue to use the pitch at the major-league level. He would never again pitch in the majors, but was permitted to continue his career legally in
minor league baseball. Minneapolis sent Shellenback to the
Vernon Tigers of the
Pacific Coast League at the close of the 1919 campaign, and Shellenback began his long career in the circuit. He would hurl for Vernon, the
Sacramento Solons,
Hollywood Stars, and
San Diego Padres, and win more than 20 games five times, with two 18-game and three 19-game winning seasons as well. All told, as a minor league pitcher, Shellenback won 315 games and lost 192 (for a winning percentage of .621), with an ERA of 3.55 over 4,514 innings. Shellenback's long tenure with Los Angeles-based teams even led to a brief movie career; he had roles in the comedies
Fireman, Save My Child (1932) and
Alibi Ike (1935). Both films starred
comedian and baseball enthusiast
Joe E. Brown, whose
son would become known as a successful baseball executive. ==Manager, coach and longtime scout==