He was not selected in the 2006 NFL draft; as such, he signed with the San Jose SaberCats of the Arena Football League in November 2006.
[1] Littlejohn saw little action as a rookie; despite this, he won his first championship when the SaberCats defeated the Columbus Destroyers in ArenaBowl XXI.
In 2009, the Arena Football League ceased operations; when it returned in 2010, Littlejohn signed with the expansion Jacksonville Sharks.
Littlejohn saw significant playing time in 2010; he responded by recording five sacks and three fumble recoveries in 13 regular season games.
In 2011, he joined the AFL's Georgia Force; there, he tallied four sacks and one fumble recovery in 12 regular season games.