None, apart from Ngatai, are particularly large men, with Aki and Nanai-Williams, the midfield partnership against the Hurricanes, one of the smallest in Super Rugby. Williams is an imposing physical presence in the No 12 jersey, an attribute which goes hand-in-hand with his offloading skills.
Some of the Chiefs management met with former All Black Williams - a revelation with the Chiefs last year - when in Sydney for the Waratahs match in April, but it's Rennie's confirmation that he is leaving a spot open for Williams next season which is most significant.
"We spent quite a bit of time with him," Rennie said. "It was test week and the Roosters weren't playing. He's been in bloody good nick and in good spirits. He enjoys the boys, he spent a lot of time around the hotel and so on, so it was good to catch up with him from that point of view."
Rennie said Williams was concentrating on the Roosters but gave positive vibes about a return next year, adding that the 27-year-old's controversial manager Khoder Nasser had given the same message.
"One thing with Khoder is that I really enjoy working with him because he is straight up. If he says something is going to happen then it happens and I find those sorts of people bloody good to deal with. He was outstanding to work with last year.
"I know people paint a picture of him being difficult but he's doing his best for his client, I guess. We found him really easy to work with. He's not greedy and he's not difficult in any way."
All Blacks lock Brodie Retallick has made a quick recovery from his hamstring injury suffered before the test against France in Christchurch a fortnight ago and will return for Rennie's men against the Hurricanes.
Nanai-Williams has recovered from a stomach ulcer and the break had also given him time to rehabilitate a groin problem, Rennie said.
The Chiefs have a longer lay-off than the other New Zealand sides because of their bye before the test window, but Rennie said the break shouldn't hurt them.
Last week at Waikato Stadium, the Chiefs had a 40-minute hitout against a Counties team followed by another 40 minutes against a Bay of Plenty side.
"It's a mindset thing," he said. "If you think it's a distraction and an issue then it probably will be, but this is where we want to be.
"We've got ourselves in a good position and there's only six weeks left in this competition. It's a chance to throw everything at it."
No 8 Ross Filipo is available again after his knee injury, with fullback Gareth Anscombe recovering from his broken foot and a possibility for next week's match.
