On June 11, 1911, it was reported that he had signed with the BC Lions of the Canadian Football League (CFL).

[4] McKinnon played in nine games for the Cleveland Thunderbolts of the Arena Football League (AFL) in 1992, totaling 27 carries for 120 yards and six touchdowns, six catches for 36 yards and one touchdown, 31 solo tackles, four assisted tackles, four sacks, one forced fumble, one fumble recovery, four pass breakups, and three blocked kicks.

[1][5] The Thunderbolts finished the season with a 4–6 record and lost in the first round of the playoffs to the Orlando Predators.

[1][5] In November 1994, the Miami Hooters traded McKinnon to the Tampa Bay Storm for Hesham Ismail, Tony Chickillo, and Travis Pearson.

[10] The Storm finished the season with a 10–2 record and eventually advanced to ArenaBowl IX, where they beat the Predators by a score of 48–35.

[5] He only appeared in three games in 1998 before he was suspended by the AFL for a year in July 1998 for violating the league's drug policy.