Competition is fierce in a number of key positions, but Ali Price is a shoo-in to start at scrum-half in the Championship opener against England on February 5.
What is not so clear-cut is who the back-up will be. Townsend opted for Price’s Glasgow Warriors team-mates Jamie Dobie and George Horne in the autumn at the exclusion of Ben Vellacott.
The Edinburgh man made an outstanding start to his career at the capital club but Townsend felt Dobie and Horne had enough credit in the bank to keep their places in the squad following the cancellation of the summer tour.
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Dobie was rewarded with his Scotland debut off the bench against Tonga in October and Horne was used as a substitute in the other three autumn Tests.
Price started all four – the only back to do so – and, injury permitting, is in the box seat to do the same in the Six Nations.
Mike Blair, Vellacott’s coach at Edinburgh and Scotland’s most capped scrum-half of all time, believes his man has done enough to warrant inclusion in Townsend’s squad but does not envy the national coach’s decision.
“It's really difficult,” said Blair. “Ben’s done really well for us, loads of positive things, and some things for him to work on. His talent is such that he’s someone Scottish fans will want involved. He’s certainly someone to get excited about.
“It depends what Gregor wants his bench to look like. Jamie’s probably the most different of those three behind Ali. He’s a really strong defender and a little bit more abrasive around the breakdown, in attack and defence. George and Ben are similar.
“I certainly think Ben is in good form at the moment and would merit involvement in the squad.”
Vellacott is averaging a try every second game since moving to Edinburgh from Wasps and possesses an explosiveness which could make him an attractive option as an impact sub.
Horne has fulfilled that role with distinction for Scotland and 14 of his 17 caps have come as a replacement. He has scored six tries for this country, but five of those came in two matches he started; a brace against Argentina in Resistencia in 2018 and a hat-trick in the World Cup match against Russia in Japan a year later.
Blair, who left his role as Scotland assistant in the summer to take the reins at Edinburgh, has taken the club to the top of the United Rugby Championship and that is likely to be reflected in Townsend’s squad on Wednesday. Blair will be happy to see as many of his players as possible selected and will keep everything crossed that they return in one piece at the conclusion of the Championship.
“There is a part of me that has sometimes thought it would be better if somebody didn't get selected, but if they are not getting selected then it potentially means they are not playing as well as they could or should,” said Blair. “I want to push our guys to get selected because it means they are playing well and we are doing a good job in our environment.”