Johnston, featured in the Under-18 Six Nations Festival staged in France in the spring, is one of nine new recruits named in Scottish under-20s head coach Kenny Murray’s 32-man squad as he rings the changes following their whitewash at the U20 Six Nations this year.
The Galashiels club were among the first to congratulate the youngster on his call-up, saying: “A huge well done to Gala’s own Kerr Johnston on being named in the U20 Scotland summer series squad.
“Kerr has worked extremely hard and Gala could not be prouder.”
The under-20s are currently in Italy for an age-grade competition running from this Friday to Tuesday, July 12, with all of Scotland’s fixtures taking place at Stadio di Monigo in Treviso.
Galashiels winger Johnston is one of a handful of Borderers in the squad, along with Melrose’s Christian Townshend, Keiran Clark and Rudi Brown, Hawick’s Rhys Tait and West Linton’s Patrick Harrison.
They’re joined by Southern Knights players Ben Afshar and Murray Redpath, the latter being Galashiels-born former Scotland captain Bryan Redpath’s son.
Murray, 48, said: “I’m really excited to be taking this group of players across to Italy for the under-20 summer series and see what they can do.
“Whilst the results in the Under-20 Six Nations were disappointing, we’ve been building on the positives that can be taken from that competition to take into this summer.
“To have had 75% of our squad getting regular game-time during the Fosroc Super6 Sprint Series, off the back of the Six Nations, has been fantastic for the players’ development.
“In training, we can see that their intensity, skill level and desire to play a good attacking style of Scottish rugby is much higher.“There are 11 members of this squad who are under 19 and to have two Scotland under-18 players stepping up to under-20 so soon after their competition in the spring is testament to the quality of players that they are.
“In both Liam McConnell and Johnston’s positions, we have a depth of talented players, so we’re keen to see how they can utilise both their physical attributes and skill-sets in this next stage of age-grade rugby.”Scotland play Wales this coming Saturday at 4pm, then hosts Italy on Thursday, June 30, at 7pm before finishing their group stage matches against Georgia on Wednesday, July 6, at 4pm.
The tournament will conclude with a cross-group match on Tuesday, July 12.
All of the Scots’ games can be seen live on YouTube.
Also in the squad are forwards Gregor Hiddleston, Duncan Hood, James Lascelles, Ali Rogers, Iain Carmichael, Gregor Scougall, Callum Norrie, Max Williamson, Jake Spurway, Josh Taylor, Tim Brown, Ollie Leatherbarrow, Euan Groenewald and Matt Deehan, plus backs Finlay Burgess, Euan Cunningham, Andrew Stirrat, Ben Salmon, Duncan Munn, Thomas Glendinning, Ryan Daley, Gabe Jones and Ross McKnight.