Longest and Shortest NFL careers by position 2.57 years just 2.57 years 2.57 years Longest and Shortest NFL careers by position with the shortest average career length average career is 3.3 years 2.57 years Longest and Shortest NFL careers by position average career is 3.3 years Studie source This article http://www.livestrong.com... 2.57 years http://www.livestrong.com/article/15…er-nfl-player/ Longest and Shortest NFL careers by position just 2.57 years Longest and Shortest NFL careers by position "Next!" shortest career spans average career is 3.3 years shortest career spans h/t Livestrong shortest career spans