His form has seen him touted as an All Black-in-waiting, with that elevation potentially arriving as early as next year.
For now, though, McKenzie has the chance to lock down the Chiefs' No10 jersey, with Rennie possibly replacing one attacking dynamo with another.
Whether that switch happens on Friday against the Force remains to be seen. Andrew Horrell, so impressive in 60 minutes against the Crusaders, could complicate the succession plan; then there's older brother Marty, who led Taranaki to an ITM Cup title last season.
"Obviously there are a few players who can play 10 in the team," McKenzie said. "So it's about training well and then, if you get a crack, trying to make the most of it. We'll see what happens."
McKenzie certainly has the biggest ceiling of any option at pivot. An elusive runner who attacks the line well with ball in hand, the diminutive Southlander has also proved a tough tackler against players who appear twice his size.
A consistent run in his preferred position would only enhance those qualities, though Rennie is unwilling to commit to the idea of one player proving to be Cruden's replacement.
"That's crystal ball gazing at this stage," the coach said. "We haven't got firm ideas that one guy is going to dominate the position now, we'll just take it as it comes.
"Damian's a hell of a talent. He's a good kid and he's working hard but he's still a young fella and got a bit to learn."
McKenzie admitted as much, paying no attention to a level of hype that has increased with every performance.
"I sit down with the coaches and I've still got plenty to work on," he said. "You try not to get too far ahead of yourself, even if you do something well. I've got plenty to work on and I'll just keep trying to improve this season if I get another crack."
Even if he exceeds the wildest expectations in that crack - think, leading the Chiefs to the Super Rugby title - it's difficult to imagine anything other than a demotion when Cruden returns next season.
That position on the depth chart, along with the Crusaders losing a trio of first fives next year, has seen some speculation that McKenzie could be the next man to wear that illustrious red-and-black No10 jersey. But, given that he signed a three-year deal in 2014, such a suggestion seems remote.
"I haven't really thought about that, to be fair," McKenzie said. "I'm loving my time at the Chiefs. The culture's awesome and I wouldn't want to leave this place at the moment."
