Donald's starring role in the thumping of Wales saw the final box ticked: the Chiefs' brains trust were convinced the World Cup winner was ready for a reintroduction to high-level rugby.
"He's had to be patient," Rennie said. "He's done a hell of a lot of training and he's been fantastic in the environment - I'm really impressed with him. The boys love him and he's made a massive contribution to our attack.
"He does a lot of the graft that allows the other players to concentrate on their performances. It's my first year involved with Beaver and I've been really impressed with him."
Rennie could have asked Damian McKenzie to play pivot against the competition leaders, returning the youngster to a position he still counts as his first choice. But McKenzie has featured exclusively at fullback in the current campaign and, having been away with the All Blacks, had little time to prepare for such a switch.
Instead, Donald will drive the Chiefs in a match they probably must win to have a good shot at securing top spot in the New Zealand conference, with Cruden waiting in the wings for a potentially crucial cameo, given Donald did cramp up late in the encounter with Wales.
Cruden will form with Tawera Kerr-Barlow and Nathan Harris an All Black-laden bench, with McKenzie, Brodie Retallick, Sam Cane and Seta Tamanivalu all backing up from international duty.
The Crusaders, meanwhile, will be missing Ryan Crotty and Luke Romano through injury, but the remainder of their All Black contingent will play a significant part. Wyatt Crockett is set to start at loosehead prop after Joe Moody occupied the position for all three tests, while Codie Taylor, Owen Franks, Sam Whitelock, Kieran Read and Israel Dagg are all included in the run-on XV.
Chiefs: Damian McKenzie, Toni Pulu, Seta Tamanivalu, Anton Lienert-Brown, James Lowe, Stephen Donald, Brad Weber; Tom Sanders, Sam Cane, Taleni Seu, Brodie Retallick, Dominic Bird, Hiroshi Yamashita, Hika Elliot, Kane Hames.
Reserves: Nathan Harris, Siegfried Fisi'ihoi, Atu Moli, Mitchell Brown, Lachlan Boshier, Tawera Kerr-Barlow, Aaron Cruden, Sam McNicol.
Crusaders: Israel Dagg, Jone Macilai, Kieron Fonotia, David Havili, Nemani Nadolo, Richie Mo'unga, Andy Ellis, Kieran Read (captain), Matt Todd, Jordan Taufua, Sam Whitelock, Scott Barrett, Owen Franks, Codie Taylor, Wyatt Crockett.
Reserves: Ben Funnell, Joe Moody, Mike Alaalatoa, Jimmy Tupou, Jed Brown, Mitchell Drummond, Mitchell Hunt, Sean Wainui.