A native of Superior, Wisconsin, Leemans played college football for Oregon's freshman team in 1932 and for George Washington from 1933 to 1935.

After his playing career ended, Leemans worked briefly as a backfield coach for the Giants and at George Washington.

[1] In his 1978 speech upon being inducted into the Pro Football Hall of Fame, Leemans recalled growing up in Superior: "I was a kid who used to work the iron ore boats on vacation from high school.

[7] As a football enthusiast, the young Mara monitored the sports sections of dozens of out of town newspapers and maintained a clippings file of prospective Giants players.

[7] Signing Leemans would be complicated by the establishment of a player draft by National Football League owners at their annual meeting in Philadelphia in February 1936.

Wellington Mara, still smitten by Leemans' running abilities, persuaded his father to make the little-known player the second round pick of the inaugural 1936 draft.

[1][11] After the season ended, Leemans reported that he found it easier to make long gains in the NFL rather than college, citing better blocking in the professional ranks.

[12] Following rumors that he intended to retire from professional football after one season, Leemans signed a contract in August 1937 to return to the Giants.

Hank Soar took over as the Giants' leading rusher in 1937, and Leemans gained only 429 rushing yards, roughly half his total from the prior year.

[13] Despite the reduced offensive output, Leemans continued to garner credit for his overall play and was selected by the NFL and the New York Daily News as a second-team player on the 1937 All-Pro Team.

[16] Leemans' attempts to enlist in the Navy and Army during World War II were rejected on multiple occasions due to defective hearing in one ear caused by a concussion sustained in a football game as well as poor eyesight.

[18] He signed on as a backfield coach with the Giants in 1943, but shortly before the season started, he opted to return as a player for one final year.

[26] He also operated a laundry and dry cleaning business in the Washington, D. C., and Silver Spring dating back to and following his years as a football player.

[4] In January 1979, less than six months after his induction into the Hall of Fame, Leemans died from a heart attack at age 66 at his condominium in Hillsboro Beach, Florida.