The Dockers are making the longest trip in the country without stars Matthew Pavlich (Achilles), Stephen Hill (quad), Nat Fyfe (suspended), and Aaron Sandilands (hamstring).
But instead of talking up his team's chance of an upset win, McKenna is reading nothing into it, saying the early-season flag fancies will bring the same level of commitment no matter who runs out.
"They certainly don't have their best 18 in or 22 … but I think the way Ross (Lyon) and most coaches like to train a side up, it's all about your structure, and personnel and name tags can change," McKenna said.
"We're under no illusions. We know what we're going to cop from Fremantle. They're going to be well drilled, hard at the footy and the tackle pressure is going to be on.
"They're number one for pressure acts in the AFL. We understand, regardless of name tags, the heat's going to be on us."
When the teams met in the corresponding match last year, Gold Coast ran the Dockers to within seven points.
They were without captain Gary Ablett on that occasion.
This time they welcome back Harley Bennell from a hamstring injury and introduce debutant Jesse Lonergan.
With a 2-3 record through five rounds, McKenna said the Suns had improved markedly on 2012 and had a message for some of the club's critics.
"Our contested ball numbers this year have been very good. From a difference point of view we're second in the AFL, which is fantastic," he said.
"Our club has been attacked about playing a certain style of football and maybe we deserved that last year. This year our difference says we're number two in the AFL and that's a good sign...
"We understand that contested footy and tackles, you win those two and you give yourselves a good chance of winning."
McKenna said Lonergan had been earmarked as a certain round one starter before breaking his wrist against Melbourne in the final pre-season match.
"He's just tenacious, he's built low to the ground and he's a solid kid. Powerful, makes good decisions and works both sides of the ball really well and he's great in a contest."
Michael Whiting covers Gold Coast news for AFL.com.au. Follow him on Twitter: @AFL_mikewhiting
