He played 13 seasons in Major League Baseball, principally as a right fielder, for the Detroit Tigers from 1933 to 1940 and the Boston Red Sox from 1941 to 1945.

[2] After graduating from high school, Fox worked at a furniture factory in Evansville and played sandlot baseball.

[3] Fox spent the 1932 season playing for the Beaumont Exporters team that won the Texas League pennant.

His teammates in Beaumont that year included Hank Greenberg, Schoolboy Rowe, Elden Auker, and Flea Clifton.

[1] In 1933, Fox joined the Detroit Tigers and became the team's regular center fielder, starting 116 games at the position.

In his first season in right field, Fox struggled at the plate with a .285 batting average, but he led the American League with four outfield double plays.

[1][5] The Sporting News in a front page profile in late July 1935 credited Fox with being the Tigers' spark plug: Super work on the part of a single player often provides the winning accelerant for a team which otherwise might remain close to mediocrity in the result column.

This season it has been Ervin (Pete) Fox, little outfielder, who has supplied the winning spark, with a recent run of 29 games in which he hit safely having witnessed the definite upswing of Mickey Cochrane's Bengals.

[2] He also ranked sixth in runs scored (116), eighth in stolen bases (14), second in times hit by a pitch (6), and fourth in range factor among right fielders (1.90).

[2] During the six-game 1935 World Series win over the Chicago Cubs, Fox led both teams with ten hits and a .385 batting average.

The reconfiguration of the outfield, combined with multiple injuries, resulted in Fox losing his position as the team's starting right fielder.

Fox suffered an "attack of lumbago" in early May, a sprained finger in July, and was called home from a road trip in August when his five-month son became ill.[8][9] Gee Walker became the Tigers' starting right fielder and Fox was relegated to a backup role, starting only 49 games in right field in 1936.

[10] The 1937 Tigers tied a major league record with four players (Fox, Gehringer, Greenberg, and Gee Walker) each compiling 200 or more hits.

On December 12, 1940, the Boston Red Sox purchased Fox from the Tigers for a sum reported to be slightly in excess of the waiver price.

[3] After his playing career ended, Fox served as a manager for minor league baseball teams in Pawtucket (New England), Waterloo (Three-I) and Hot Springs (Cotton States).

Don became a pitcher in the Boston Red Sox organization, and James became an all-city football player at his father's alma mater, Bosse High School.