PACK aces Taniela Tupou and Izack Rodda have been forced to rest from Saturday's Super Rugby clash in Tokyo, which makes the Queensland Reds look even riper for an ambush.

In accordance with Rugby Australia's workload management policy this year, the Wallabies pair have been rested from the match against Japan's Sunwolves.

Coach Brad Thorn revealed the Round 5 clash was a "pre-determined rest match" for the duo who are an important  part of the physical and scrummaging heart of the Reds.

After three losses to start Super Rugby, the Reds are already rare underdogs against the Sunwolves, who thrashed the Queenslanders 63-28 in the corresponding match in Tokyo last year.

The Reds have made five changes to their starting XV with young Isaac Lucas, 20, being shifted to the hot seat at flyhalf in just his fourth Super Rugby game.

The absence of scrum powerhouse Tupou means Ruan Smith will partner twin brother JP in the front-row.

Rodda's spell is covered by Angus Scott-Young coming into the backrow and Lukhan Salakaia-Loto shifting from the backrow to lock.

Alex Mafi, after prominent minutes off the bench against the NSW Waratahs, will start at hooker ahead of Wallaby Brandon Paenga-Amosa.

Hamish Stewart is back in the starting side at fullback.

"Our performance was disappointing last week in Sydney. We can't afford another slow start," Thorn said.

"The Sunwolves are a side who have improved greatly in the past two years.

"This week is a pre-determined rest match by Rugby Australia for those two players (Tupou and Rodda).

"We've got good depth with Ruan and Angus able to slot straight in there, as well as having Lukhan's versatility across the second and backrow.

"We've decided to rest Bryce this weekend to let him recover from a niggling rib injury.

Isaac has played some quality Rugby in his three appearances this season. He's played at 10 for most of his junior footy, so this is nothing new for him.

REDS V SUNWOLVES

Prince Chichibu Memorial Stadium

Tokyo, Saturday 2.15pm

1. JP Smith - GPS

2. Alex Mafi - Bond University

3. Ruan Smith - GPS

4. Harry Hockings - University of Queensland

5. Lukhan Salakaia-Loto - Souths

6. Angus Scott-Young - University of Queensland

7. Liam Wright - Easts

8. Scott Higginbotham - Wests

9. Moses Sorovi - Wests

10. Isaac Lucas - Sunnybank

11. Sefa Naivalu - TBC

12. Duncan Paia'aua - Norths

13. Samu Kerevi (c) - Souths

14. Chris Feauai-Sautia - Souths

15. Hamish Stewart - Bond University

16. Brandon Paenga-Amosa - Sunnybank

17. Harry Hoopert - Brothers

18. Feao Fotuaika - Souths

19. Angus Blyth - Bond University

20. Caleb Timu - Souths

21. Tate McDermott - University of Queensland

22. Teti Tela - Souths

23. Filipo Daugunu - Wests