After starting his career in semipro ball in New Jersey in 1928, he was signed by the Philadelphia Athletics and hit .404 to win the Blue Ridge League batting championship in 1929.

He played with the Athletics' powerful championship teams of 1929–1931, breaking in gradually, though in the postseason for the A's he appeared only twice, as a pinch-hitter, in the 1931 World Series.

Al Simmons and Jimmy Dykes were sold to the Chicago White Sox on the same day in September 1932, and Lefty Grove and Mickey Cochrane were traded away after the 1933 season.

Two years after hitting over .300 for the last time with the 1943 Tigers, Cramer played 140 games in center field at age 40 in 1945 (albeit during World War II, when many regular players were in military service), and finally enjoyed significant play in the Fall Classic that year, leading the Tigers in the 1945 World Series with a .379 batting average, scoring seven runs and knocking in four, to help them win the Series 4–3 over the Chicago Cubs.

Cramer was walked to load the bases and set up a force play, but Greenberg followed with a grand slam that won the pennant for the Tigers.

[4] As White Sox batting coach from 1951 to 1953, he tutored the young second baseman Nellie Fox, who often credited Cramer with making him a major league hitter.

[5] He died in the Manahawkin section of Stafford Township, New Jersey, at 85 years of age, where a street, Doc Cramer Boulevard, is named in his honor.