McKenna said last Saturday's 40-point win over powerhouse Geelong was "a fork in the road" and he was looking forward to the Suns having a chance to repeat the dose against Hawthorn in Launceston this weekend.
The Hawks taught their young rivals a lesson earlier this year, smashing them by 99 points at Metricon Stadium.
McKenna said the Suns could no longer use physical underdevelopment as an excuse against the heavy hitters after disposing of the Cats.
"It made me realise the boys are a bit more physically advanced than I thought they were," McKenna said.
"To take Geelong on at their own game, it was a fork in the road so to speak, and they got through it OK. That was pleasing.
"Regardless of who we're playing, whether it's a top-four side or a bottom-four side, it's about mentally and physically replicating that, and we have to do that for at least nine weeks."
The two teams have changed significantly since the round four clash, and McKenna says the Suns are now in better form.
Harley Bennell, Jack Martin and Zac Smith did not play the premiers earlier this year, while the Hawks did not have Brian Lake but will miss Sam Mitchell and Josh Gibson from the earlier clash.
Gold Coast will be without in-form small forward Brandon Matera for up to two weeks, after the goal-sneak failed to recover from an adductor injury suffered at the weekend.
"I just think it's a great chance for us to test ourselves against a side that did blow us off the park on our own deck, and give us a really good assessment of where we're at," McKenna said.
"It's a great test for us to back up the same effort we had last week and that should give the boys some confidence - it's given the coaching group some confidence."
Twitter: @AFL_mikewhiting
