Flanker and captain Peter Rowe, No8 Darren Munro and prop Shaun McDonough will be doing the tough stuff in the engine room, while Nic Cranston and Fraser Hammond look to make an impact off the bench.
Back said Samoa A had toured New Zealand earlier this year to gain experience against the Super 15 development squads.
"It's the best of the rest, local wise, who don't make the Manu Samoa side."
The Heartland boys are under no illusions that it is a big day for the islanders and their supporters, as the national side also take on Canada this morning in Wales.
Samoa A is guided by former Samoan test legend Brian Lima.
"With his coaching, there will be no love lost in the tackle and ruck area," Back said.
Despite an expected crowd of 3000-4000, Apia Park more closely resembles Cook Gardens, with a little running track gap between the field and rabid fans, unlike the cauldron atmosphere the Wanganui boys experienced in Ruatoria.
Back said while it was their own mistakes that beat them against Apia, everything had been building to the test and the team wanted to finish the tour strongly.
"As someone said at training, 'it doesn't matter if you're 19 or 36, it could be the last time you wear the Silver Fern'."
Heartland team
1. Mat Fetu; 2. Ngarimu Simpkins; 3. Shaun McDonough; 4. Ben Coman; 5. Aarin Dunster; 6. Sione Ngatu; 7. Peter Rowe (captain); 8. Darren Munro; 9. Andrew Stephens; 10. Mark Davis; 11. Nathan Hunt; 12. Fa'aitu Tuamoheloa; 13. Pomare Samupo; 14. Tau Moeke; 15. Billy Guyton.
Reserves
16. Nathan Tubbs; 17. Ralph Darling; 18. Nic Cranston; 19. Fraser Hammond; 20. Ben Draper; 21. Lemisio Masoe; 22. Cameron Hayton.
