Meanwhile, winger Gabriel Hamer-Webb is set to make his Test debut. The former Cardiff ace is included in a fresh-looking squad, with Sam Costelow, Ben Carter and Taine Plumtree drafted into the run-on group, while Freddie Thomas, James Botham and Blair Murray come onto the bench.
Wales head into Saturday's Test at the Principality Stadium looking for their first win of the Six Nations, following heavy defeats to England and France in their opening two rounds.
Debutant Hamer-Webb is the only new face in the Welsh back-three, as Louis Rees-Zammit and Josh Adams get the nod once again this weekend, while centre duo Eddie James and Joe Hawkins also keep their spots. Fly-half Costelow now partners Tomos Williams in the playmaking axis, with the Gloucester ace again starting at scrum-half.
Plumtree's return at blindside sees Aaron Wainwright moved back to number eight, while Alex Mann shifts over to openside. Carter's introduction for Adam Beard sees him partner Dafydd Jenkins in the locks.
Rounding off the run-on group, Tomas Francis, captain Dewi Lake and Rhys Carre continue in the starting front-row.
The trio of Thomas, Botham and Murray also join Ryan Elias, Nicky Smith, Archie Griffin, Kieran Hardy and Jarrod Evans on the bench.
Commenting on his selection, Tandy said: "There are some changes to the team this week. We feel this is the best team to take on Scotland and with a six-day turnaround you want some freshness as well going into the game.
"It's our third game of the championship. We want to build on our performance. We want to see more consistent moments and back-to-back moments, which we feel if we get we'll be closer to getting the outcome we want from games."
"Then when you dig into his background at Leicester, even when he wasn't in the team, everyone said he was an amazing team player. He also kept pushing, he never gave up and then when he had his Leicester opportunity he took it with two hands and now this opportunity has come up and it's thoroughly deserved."
Wales - 15 Louis Rees-Zammit, 14 Gabriel Hamer-Webb, 13 Eddie James, 12 Joe Hawkins, 11 Josh Adams, 10 Sam Costelow, 9 Tomos Williams, 8 Aaron Wainwright, 7 Alex Mann, 6 Taine Plumtree, 5 Ben Carter, 4 Dafydd Jenkins, 3 Tomas Francis, 2 Dewi Lake (c), 1 Rhys Carre.
Replacements: 16 Ryan Elias, 17 Nicky Smith, 18 Archie Griffin, 19 Freddie Thomas, 20 James Botham, 21 Kieran Hardy, 22 Jarrod Evans, 23 Blair Murray.
France head coach Fabien Galthie has opted to largely stick with the side that ran rampant over Wales last weekend, making only minor adjustments aimed at strengthening the scrum for their clash with Italy.
Head Coach Gregor Townsend has made five changes to his starting team ahead of Saturday's Six Nations match against Wales at the Principality Stadium in Cardiff.
Ireland head coach Andy Farrell has axed Sam Prendergast for the Six Nations clash against England at Allianz Stadium, Twickenham, on Saturday.
England captain Maro Itoje will earn his 100th international cap when he leads the side against Ireland at Allianz Stadium, Twickenham on Saturday, with head coach Steve Borthwick making five changes to his lineup.
