Melbourne Rebels have named two Japan internationals in their Super Rugby squad for the first time, with Male Sa'u and Shota Horie on the bench for the match against New South Wales Waratahs in Sydney on Friday night.

Sa'u, a centre with 13 Test caps, is in line for his first appearance after the Rebels made two injury-enforced changes to the run-on side: fullback Jason Woodward and prop Laurie Weeks have been sidelined by a knee injury and concussion, with Angus Roberts and Paul Alo-Emile their respective replacements.

Winger Lachlan Mitchell, who will become the first player to play 50 Super Rugby games for the Rebels, said the changed team was desperate to beat the Waratahs again after claiming their first last season.

"That's one of my biggest games, to beat the Waratahs, it's great to rub it in," Mitchell said, while Scott Higginbotham said the Rebels "want that feeling again".

"That was a significant win for the club and we're going there to keep that Weary Dunlop Shield," Rebels captain Higginbotham said.

Mitchell is under no illusions that victory will come easily, however, saying "you have to be prepared because you're basically just playing the Wallabies ... you have to be switched on because they don't really have any weaknesses."

Higginbotham said the Rebels had watched how the Brumbies stymied the Waratahs in Canberra, saying "it's about shutting it down before they can get on the front foot".

"Defence is going to be very important because when they get front-foot ball, they can put guys like Peter Betham and Israel Folau through the holes."

Waratahs assistant coach Daryl Gibson, meanwhile, said the 28-23 defeat in Canberra could prove to be a blessing, saying "iIt's been an absolute gift that we got that, a little bit of a wake-up call, a reminder that we're not as good as we think we are, and what is required to do well in this competition".

"While we're disappointed to lose against the Brumbies, it certainly showed us what's required to, firstly, top the Australian Conference but then also looking towards making a bigger impact on the competition," Gibson said.

"And probably if you asked every team in the competition, they would say they would want to finish in the top two because they know that's where you need to be to win the competition. This year with the squad we've got, we've absolutely got to set our ambitions high."

Waratahs coach Michael Cheika said the Waratahs' squad had "all been a little bit grumpy, a bit edgy" leading up this week's latest Australian derby. "No one likes losing, but it keeps you grounded and far more urgent about going about your preparation."

Waratahs: Israel Folau; Alofa Alofa, Adam Ashley-Cooper, Kurtley Beale, Peter Betham; Bernard Foley, Nick Phipps; Dave Dennis, Michael Hooper, Jacques Potgieter, Kane Douglas, Will Skelton; Paddy Ryan, Tatafu Polota Nau, Sekope Kepu. Replacements (from): Tolu Latu, Jeremy Tilse, Benn Robinson, Wycliff Palu, Stephen Hoiles, Brendan McKibbin, Rob Horne, Matt Carraro, Pat McCutcheon, Jonno Lance.

Rebels: Angus Roberts; Lachlan Mitchell, Tamati Ellison, Mitch Inman, Tom English; Bryce Hegarty, Luke Burgess; Scott Higginbotham (captain), Scott Fuglistaller, Sean McMahon; Luke Jones, Hugh Pyle; Paul Alo-Emile, Pat Leafa, Toby Smith. Replacements: Shota Horie, Max Lahiff, Cruze Ah-Nau, Cadeyrn Neville, Colby Fainga'a, Ben Meehan, Male Sa'u.