Throughout Super Rugby Aotearoa and the opening round of Super
Rugby Transtasman, the Chiefs have used five different wing combinations, with Etene Nanai-Seturo and Jonah Lowe combining in six on the side's 10 games this year.
However, with Nanai-Seturo now in the All Blacks Sevens system in preparation for the Olympics, McMillan is still trying to find someone in his squad who will make the vacant starting spot their own.
"In the backs, particularly around our back three, for a good portion of the season you've seen a little bit of rotation there," McMillan said.
"It's been frustrating for the players and it's been frustrating for the coaches that no one has really taken the opportunity to bang the door down and say 'this is my jersey'."
After running Lowe and Shaun Stevenson in the starting wing positions for last weekend's win over the Western Force in Perth, the Chiefs will roll out their sixth combination of the year when they pair Lowe with Bailyn Sullivan in Hamilton on Saturday night.
"It's not that Shaun played poorly last week," McMillan explained of the change. "We're just searching for that person to put their hand up and say 'hey, I'm the guy'. It's a little bit of a Ferris wheel there and hopefully sooner rather than later we settle on a combination."
While the Chiefs have made changes elsewhere in the squad, McMillan said in some areas they have had their hand forced due to injuries, while they have also taken into account the added demand of travel that comes with Super Rugby Transtasman.
"We definitely have looked at the next four weeks different to the Super Rugby Aotearoa competition where you know things are going to be brutal but you don't really have to worry about the travel demands and it doesn't really impact on your training week whereas this is different," he said.
"We know we've got an arduous four weeks ahead of us, but we don't want to make excuses or anything, we've just got to embrace it, make the most of it and get out there and play."
Sullivan's addition is one of four changes to the run-on side for the opening round. Sione Mafileo starts at tighthead prop in place of Angus Ta'avao who is nursing a hip injury, Samisoni Taukei'aho starts at hooker, while veteran loose forward Liam Messam starts at blindside flanker.
On the bench, All Blacks prop Atu Moli is set to make his first appearance of the year after an ongoing hip issue, while Bradley Slater, Rameka Poihipi and Kaleb Trask have also been included on the bench after missing last weekend's game.
