Then there was his match-sealing try, which demonstrated his athleticism and speed.
"The big fella's pretty impressive," Rennie said. "If you look at the amount of work he gets through, the numbers are phenomenal.
"Because he carries and carries aggressively, he can square up defences, but he's good enough to shift the ball and throw it out the back door. He's massive for us."
Retallick was relentless throughout last month's English series, continuing the rapid rise he has made on the international scene since making his All Blacks debut two years ago.
His continuous presence in the starting XV, along with the work rate he brings to every match, means the Chiefs have been careful to avoid over-burdening their prize asset, wary that his one-speed style could create burn out. In that regard, a week with minimal training, due to a hip injury in the Highlanders game, might have been a good thing.
"We're conscious of the fact that he has played a lot of footy," Rennie said. "But he's in pretty good nick. He didn't train in the week so that was probably why he was full of energy."
For his part, Retallick was happy to focus on the production of the rest of the forward pack, reluctant to agree he was playing at a level approaching the peak of his powers.
"I'm not sure about that," he said. "I'm always trying to get better and we needed a big performance from everybody. I'm just trying to do my best and do my job out there.
"We wanted to out-muscle [the Hurricanes] up front and we had talked about how long it had been since our forward pack had dominated or got the edge on the opposition forward pack. I think it was a step in the right direction, especially with the playoffs coming up."