Niggling injuries have forced trio Jack Maddocks, Anaru Rangi and Matt Philip out of the Rebels team to face the Sunwolves at AAMI Park on Friday.
Rebels coach Dave Wessels said Maddocks (knee), Philip (heel) and Rangi (ankle) could probably have lined up at a pinch but perhaps not performed at the intensity he wants as Melbourne search for their first win this season against a South African side.
"We want to put in a really good performance this weekend and I think those guys were fit to play, but were they really fit to perform in the real sense?
"I think we've got to have faith in the wider squad," Wessels said.
The Rebels are hoping a week on the sidelines will be enough to help settle Maddocks' patella tendinitis, while his workload in the front half of the season has also suggested he is ready for a rest.
"He's also played seven games in a row and had a lot of minutes, so we thought it was appropriate for him to have a rest," Wessels said.
"I think also those decisions are made much easier when a guy like Semisi (Tupou) trains as well as he does and also plays as well as he did in the minutes he got against the Sunwolves, so he's a really exciting prospect for us too."
Philip, who has a bruised heel, will be replaced by Ross Haylett-Petty at lock, while Robbie Abel will start at hooker for Rangi who was forced from the field in the Sunwolves match with a rolled ankle.
Having started his career with the Stormers as an analyst, there's personal pride on the line for Wessels on Friday, as well as a chance for the Stormers to increase their lead at the top of the Australian conference ahead of next week's derby against the Waratahs.
But Wessels insisted his side wasn't looking too far ahead.
"I don't think the Stormers played particularly well against the Reds last week and I think they'll be frustrated by that, which is dangerous for us.
"They very nearly beat the Hurricanes and I thought they played well in large parts against the Blues, so they're a good side.
"We haven't given much thought to the Waratahs yet, we've got a huge game this weekend.
"We were disappointed with our performances in South Africa, we obviously lost on the hooter against the Lions at Ellis Park and then really didn't play well against the Sharks in Durban.
"We haven't beaten a South African team yet this year and I think that opportunity is a marker for us - a mini-milestone in our season - so we're very keen to make a statement with our performance."
Sam Talakai returns after missing the Sunwolves game and with Abel and Tetera Faulkner, faces a challenge against a monster Stormers pack.
"The Stormers do provide some challenges that maybe we haven't had in our last two games," Wessels said.
"I think we've got to get those things right.
"They've got a really world class front row, so that's a huge challenge for our pack and I think one that our guys will be up for.
"Probably to combat some of their strengths at set piece time we've chosen a slightly heavier front row to go into this game.
"I thought Jermaine Ainsley played very well, probably his best game for us in a while, starting last week against the Sunwolves, and then Hugh Roach made a real impact when he came off the bench.
"So we'll look to up the tempo towards the back end of the game."
Rebels to face Stormers:
1 Tetera Faulkner
2 Robbie Abel
3 Sam Talakai
4 Ross Haylett-Petty
5 Adam Coleman
6 Luke Jones
7 Angus Cottrell (c)
8 Isi Naisarani
9 Will Genia
10 Quade Cooper
11 Marika Koroibete
12 Billy Meakes
13 Tom English
14 Semisi Tupou
15 Reece Hodge
16 Hugh Roach
17 Matt Gibbon
18 Jermaine Ainsley
19 Esei Ha’angana
20 Rob Leota
21 Richard Hardwick
22 Michael Ruru
23 Campbell Magnay