Donlon won the NJ State Class A 100 Yard Dash in 1921 for Trenton High.  He was the 1921 city champion in the 100 Yards as well.  After graduating from Trenton High, he attended Trenton State Teachers College (TCNJ) where he captained the track and field team.  He was also a member of the Trenton Times AA Track Club and won 2 AAU Middle Atlantic States 100 Yard Dash titles.  

Donlon competed regularly until the early 1930s.  In 1932 he became Athletic Director at Rider University where he additionally coached track, soccer and basketball.