Tait in centre stage for Scotland U20
Scotland will field three new U20 caps in the IRB Junior World Championship opener against Australia in Argentina on Saturday.
Scotland U20 head coach Eamon John said: "The groups probably don't get much tougher than ours [Australia, South Africa and Tonga] - the balance of skill and physicality make it a very interesting group.
"It's very tough and very demanding but that's what it's about, we've got to see which players in our system can go and compete at a world level."
Promoted from the U19 set-up, Robert McAlpine will partner fellow West of Scotland lock Robert Harley who, like centre Alex Dunbar, will play in his 11th straight U20 match having started every game in last season's World Champions in Japan and this season's Six Nations.
Michael Tait, son of Scotland and British Lion, Alan Tait, will debut at outside-centre having missed the Six Nations with a foot injury, while Alex Black will forge a halfback partnership with flyhalf Duncan Weir.
Elsewhere in the side, back three trio Tom Brown, Oliver Grove and Dougie Fife start their sixth successive U20 match together having featured in every game in 2010 Six Nations.
Hooker, Alun Walker, is joined by props George Hunter and Nicky Little while the familiar back row of Michael Maltman and David Denton are steered by captain and No.8 Stuart McInally.
Scotland: 15 Tom Brown, 14 Oliver Grove, 13 Michael Tait, 12 Alex Dunbar, 11 Dougie Fife, 10 Duncan Weir, 9 Alex Black , 8 Stuart McInally (Captain), 7 David Denton, 6 Michael Maltman, 5 Robert McAlpine, 4 Robert Harley, 3 George Hunter, 2 Alun Walker, 1 Nicky Little.
Replacements: 16 Adam Fedorciow, 17 Anthony Kent, 18 Callum Stidston-Nott, 19 Michael Fedo, 20 Russell Weir, 21 Matthew Scott, 22 Callum MacBurnie.
Date: Saturday, June 5
Venue: Estadio CA Colon, Santa Fe
Kick-off: 16.00 (12.00 GMT)
Referee: Pascal Gauzere (France)
Assistant referees: Francisco Pastrana (Argentina), Joaquin Montes (Uruguay)