Most important of all is the barrel-chested South African WP Nel, who is in with a shout for the Lions if he can rediscover the form of 2016.Neck injuries and props don’t go well together even if, to borrow from Cotter, we were surprised to discover that Nel had a neck to injure.
Thankfully the tighthead turned out for Edinburgh yesterday and he should get more game time under his belt before Ireland visit Murrayfield on 4 February. You have to hope so because the Irish front row, Jack McGrath, Rory Best and Tadhg Furlong, has a Lions look about it.
Zander Fagerson will be in the mix but Scotland do not have a third international class tighthead to call upon and if Cotter insists on picking three, Moray Low is unlikely to be included after his last outing against Georgia resulted in a yellow card.
One man who won’t make the start of the tournament is Alasdair Dickinson, who returned after a six-month break with a hamstring injury only to be signed off again after 33 minutes of the 1872 Cup with a broken bone in his foot – frustrating times because Dickinson has lost none of his scrummaging prowess. He will miss the opening two rounds of the Six Nations, possibly more. The starting spot looks like a straight fight between Allan Dell, Gordon Reid and Alex Allan, the former the man in possession who improved throughout the autumn series.
Locks mostly look after themselves, with brothers Richie and Jonny Gray in pole position and Ben Toolis the coming man. Big, physical and dynamic with it, he may have edged ahead of his rivals, with Grant Gilchrist currently operating well below his best.
The back row of the scrum will cause some late-night arguments, although we can expect Hamish Watson, John Hardie (injury allowing), John Barclay, Ryan Wilson, Josh Strauss and Rob Harley to be named, with Marcus Bradbury a possibility.
Cornell du Preez has been badly affected by a long-term ankle injury he can’t shake and the Six Nations is no place for a one-legged flanker.
Scrum-halves probably pick themselves, with Greig Laidlaw in pole position backed up by Henry Pyrgos and Ali Price, who has a decent chance of making the bench if only because he offers a contrast in styles from the Scotland skipper.
The same is true one wider at stand-off, where Duncan Weir boasts a different skill set to Finn Russell and, in the enforced absence of the injured Peter Horne, may get the bench spot ahead of Harlequins’ Ruaridh Jackson, who has managed two starts plus four more appearances off the bench for his Premiership club this season.
The back three are culled from four players – Stuart Hogg, Tommy Seymour, Tim Visser and Sean Maitland – and anyone else who is picked is unlikely to feature, injuries excepting. Seymour has been the number one winger for a while now but he has shown some worrying defensive lapses of late.
He was largely responsible for Georgia’s opening try at Rugby Park and he also made an error of judgment which allowed the Cardiff Blues’ winger Blaine Scully to sneak in and score against Glasgow last weekend.
However Seymour has the happy knack of scoring and he is excellent in the air, so he should continue his run in Scotland’s starting XV.
And finally to the midfield where Scotland boast such an embarrassment of riches that there is no guarantee that Mark Bennett, Scotland’s second most incisive back, and Matt Scott, who has eight tries for Gloucester this season, will both make the squad.
Huw Jones has recovered from the foot injury he suffered against Argentina in the autumn Tests and Duncan Taylor has eventually recovered from the hamstring he tore on tour in Japan. His return to Saracens last weekend was spoiled by a head injury after just 13 minutes.
Although he is not named in the Sarries’ squad for today’s match against Scarlets, Taylor should be good to go against Ireland.
Alex Dunbar is the specialist 12, which leaves everyone else squabbling over the number 13 shirt with Taylor in pole position provided he can prove his fitness between now and the beginning of February.