The 24-year-old, who has been capped seven times by Tonga, most recently represented his country in July’s Pacific Nations Cup and has been signed from New Zealand provincial side Southland.
Melrose-born Grant Shiells starts at loosehead with Neil Cochrane at hooker and John Andress at tighthead. Locks Anton Bresler and Fraser McKenzie are joined in the pack by Scotland under-20 captain Jamie Ritchie on the blindside, Roddy Grant at openside and Cornell Du Preez in the No 8 jersey.
Nick McLennan takes the full-back berth with Jamie Farndale and Tom Brown on the right and left wings respectively. The centre pairing of Chris Dean at 13 and Andries Strauss at 12, with Phil Burleigh at stand-off and Nathan Fowles at scrum-half completes the backs.
Grant will captain the side and said: “Playing against a national team is something a bit different so it will be an interesting game.
“They are preparing for the World Cup so it’s going to be a good test for us.
“It’s great to go down to Melrose and play because we get a lot of people from the Borders coming up to our games.
“It’s good to go down to them for a change and hopefully it might convince a few more to head up to Edinburgh and watch us in the new season.”
Scotland under-20 flanker Magnus Bradbury features on an expanded bench along with new scrum-half Murdo McAndrew. Prop Allan Dell, who is part of the extended Scotland squad, is available to play in the match.
Edinburgh team: N McLennan; J Farndale, C Dean, A Strauss, T Brown; P Burleigh, N Fowles; G Shiells, N Cochrane, J Andress, A Bresler, F McKenzie, J Ritchie, R Grant (c), C Du Preez. Subs: J Hilterbrand, G Turner, J Cosgrove/A Dell, S Berghan, A Toolis, M Bradbury, M McAndrew, J Te Rure, S Beard, J Johnstone, O Katoa, J Cuthbert.