"We had a big training week last week,' Rennie said. "We had a local guy with us for the week [leading up to the Cheetahs match] and he was surprised how hard we worked the boys."
This week has not been so intense, so Rennie does not envisage any tired bodies with thoughts of home further weighing them down.
The Chiefs want to play a fast game against the Sharks. That's not a startling revelation, but it does mark a shift from their approach against the Cheetahs where they tried to suck the expansive home side into a tighter game than they would have liked.
"The Sharks are a traditional South African side, big and strong upfront and a little more belligerent than other sides.
"They will be keen to take us on in the forward pack," assistant coach Tom Coventry said.
The Sharks will be confrontational at the set-piece and the tackle area but the Hurricanes showed that they don't have effective answers to teams that have the ability to launch counter-strikes. Territory and possession are not necessarily as important against the Sharks as is the ability to shift the ball quickly.
Rennie has made a few changes from the team that won in Bloemfontein as the Chiefs chase a record seven wins in succession.
Flanker Sam Cane ousts the hard-working Tanerau Latimer from the starting 15. Latimer has been playing with an iffy Achilles tendon but is fit enough for the reserves.
As has become a tradition, the roles of the hookers has been reversed, with Mahonri Schwalger starting this week and Hika Elliot asked to make an impact off the pine.
Asaeli Tikoirotuma replaces Tim Nanai-Williams on the wing. Williams has been struggling with a groin injury and the coaching staff felt a complete rest would be beneficial.
There is no rest, however, for try-scoring freak Sona Taumalolo and co-captains Craig Clarke and Liam Messam.
The trio have clocked up some serious minutes over the first half of the competition, but Rennie does not see any signs of fatigue just yet.
"We've certainly looked at it. Physically the guys are in really good shape. They're pretty happy with where they're at," he said.
Prop Toby Smith was once again not considered as he battles back from a leg injury suffered in the first-round defeat to the Highlanders.
Rennie said they were still "managing" Smith through trainings and did not feel it was wise to bring him in too early. If he'd been back in New Zealand he would have been assigned to club duty this weekend.
Sharks v Chiefs
Durban, 3.05am tomorrow
Riaan Viljoen
Louis Ludik
JP Pietersen
Tim Whitehead
Lwazi Mvovo
Patrick Lambie
Charl McLeod
Keegan Daniel (c)
Willem Alberts
Jacques Botes
Anton Bresler
Steven Sykes
Jannie du Plessis
B. du Plessis
Dale Chadwick
Craig Burden, Wiehahn Herbst, Pieter-Steph du Toit, Jean Deysel, Marcell Coetzee, Meyer Bosman, Frederic Michalak.
Andrew Horrell
Lelia Masaga
Richard Kahui
Sonny Bill Williams
Asaeli Tikoirotuma
Aaron Cruden
T. Kerr-Barlow
Alex Bradley
Sam Cane
Liam Messam
Brodie Retallick
Craig Clarke (c)
Ben Tameifuna
Mahonri Schwalger
Arizona Taumalolo
Hika Elliot, Josh Hohneck, Michael Fitzgerald, Tanerau Latimer, Augustine Pulu, Jackson Willison, Robbie Robinson.
Recent form
Sharks
* beat Blues 29-23 (a)
* lost to Hurricanes 18-42 (a)
* beat Brumbies 29-26 (a)
* lost to Waratahs 30-34 (a)
* beat Reds 27-22 (h)
Chiefs
* beat Cheetahs 39-33 (a)
* beat Force 20-12 (a)
* beat Waratahs 30-13 (h)
* bye
* beat Brumbies 29-22 (h).