Harvey Preston makes his first start for Scotland Men U20. (SNS/Scottish Rugby)
Harvey Preston comes into the starting XV, having come off the bench in the opening two fixtures. He comes in at openside flanker, replacing Jack Utterson who misses out through injury.
In an unchanged front row, loosehead prop Jamie Stewart is joined in the front row by hooker Joe Roberts, who vice-captains the side, and tighthead prop Ollie Blyth-Lafferty.
Christian Lindsay and Alfie Blackett continue in the second row, while Sam Byrd at blindside flanker, and Rory Purvis at number 8 join Preston in the back row.
Hamish MacArthur continues at scrum-half, and is again partnered by Jake Dalziel at stand-off to complete the half-backs.
Captain Ross Wolfenden is again selected at inside centre, with Campbell Waugh on his outside. Nairn Moncrieff is on the right wing, with Rory McHaffie on the left, and Henry Widdowson again starts at full-back.
There are two potential debuts in the forward replacements. Archie Appleby, a late addition to the wider training squad, is primed to come on in the second row, while back row Jack Marshall returns from injury to make his first matchday squad. Hooker Jamie McAughtrie, props Oliver McKenna and Jackson Rennie and second row Fin Ronnie are the other forward replacements.
The lineup is completed by Adam McKenzie and Calum Jessop, who return as the two backs replacements in a 6-2 bench split.
Scotland U20 team to play Wales U20 at Cardiff Arms Park on Friday (kick off 7.15pm) – live on BBC iPlayer and the BBC Sport website.
15. Henry Widdowson (Edinburgh Rugby)
14. Nairn Moncrieff (Edinburgh Rugby)
13. Campbell Waugh (Glasgow Hawks)
12. Ross Wolfenden – Captain (Edinburgh Rugby)
11. Rory McHaffie (Edinburgh Rugby)
10. Jake Dalziel (Merchiston Castle School/Melrose RFC)
9. Hamish MacArthur (Edinburgh Rugby)
1. Jamie Stewart (Edinburgh Rugby)
2. Joe Roberts – Vice-captain (Glasgow Warriors)
3. Ollie Blyth-Lafferty (Edinburgh Rugby)
4. Christian Lindsay (Edinburgh Rugby)
5. Alfie Blackett (Cardiff Metropolitan University)
6. Sam Byrd (Edinburgh Rugby)
7. Harvey Preston (Glasgow Hawks)
8. Rory Purvis (Glasgow Warriors)
Replacements
16. Jamie McAughtrie (Ayr RFC)
17. Oliver McKenna (Glasgow Warriors)
18. Jackson Rennie (Glasgow Warriors)
19. Archie Appleby (Northampton Saints)
20. Fin Ronnie (Watsonian FC)
21. Jack Marshall (Saracens/Loughborough University)
22. Adam McKenzie (Watsonian FC)
23. Calum Jessop (Heriot’s Rugby)