He formed one of the most feared backlines in the AFL, along with John Worsfold, Ashley McIntosh, Glen Jakovich and Michael Brennan and was known for his cool demeanour and reliability.

[5][6] McKenna boasts two unusual on-field distinctions from his career: In Round 20, 1994, he was the first player ever ordered from the ground under the blood rule, which had been introduced to the league that week.

[7] Then, in a match against St Kilda in Round 22, 1999, for the first time since Essendon's Jack Clarke in 1958, McKenna became the third captain in league history to call for a headcount; however, the teams were even.

[12][13] In 2008, McKenna was appointed the inaugural senior coach of the newly founded Gold Coast Suns Football Club.

[17] In the 2012 season, the Gold Coast suns under McKenna finished in seventeenth position (second-last) on the ladder, yet again with three wins and nineteen losses.

In the 2013 season, the Gold Coast Suns under McKenna improved on-field performance when they finished fourteenth on the ladder with eight wins and fourteen losses.