How 'dark horses' Scotland recover from ultimate Six Nations hammer blow and options available

And it still might. But the revelation on Monday that Sione Tuipulotu will miss the entire Six Nations is as savage a blow as they come. The Scotland captain suffered a training injury so serious last week that he will require surgery to repair his pectoral muscle.

This particular bad news bulletin delivered another bombshell: Scott Cummings, a certain starter in the second row, is also likely to miss the tournament after fracturing his arm during Glasgow Warriors’ loss to Harlequins in the Champions Cup on Saturday night.

First and foremost, it is devastating for the players, both of whom are mainstays of the national side and in exactly the sort of form you would wish going into the championship. Tuipulotu in particular is in his absolute pomp. Man of the match for Glasgow in their victory over Racing 92 last week, he is never less than inspiring for club and country.

He has embraced the Scotland captaincy and used it to elevate his game to new levels. His centre pairing with Huw Jones is the envy of world rugby, a devastating combination which enriches both Glasgow and Scotland. It’s a duo that has Lions tour written all over it and the hope is that Tuipulotu can at least recover in time for that.

The initial diagnosis is that he is “expected to return to action before the end of the season”. But not in time for the Six Nations, sadly. His absence will sap much of the feelgood factor from Scotland's supporters and will do little to enhance the team’s chances of ending their 26-year wait to win the championship.

No replacements have been called up at this stage for either Tuipulotu or Cummings but that might yet happen in the build up to the tournament or as it unfolds. Scotland open their campaign with back-to-back home games, against Italy and Ireland on February 1 and 9, then play England away, Wales at home and France away.

The captaincy will now be shared by Finn Russell and Rory Darge, roles they performed in last season’s Six Nations with mixed results: wins over Wales and England and defeats by France, Italy and Ireland. The pair had originally been named as vice-captains for this year’s tournament but were hastily promoted when the extent of Tuipulotu’s injury became apparent.

Last year’s experience will stand them in good stead and Russell in particular will relish the responsibility. The stand-off is the most capped player in the squad, having played 82 times for Scotland and been involved in 10 Six Nations Championships.

The question now for Gregor Townsend is how he replaces the world class talent at 12. The simple answer might be to look no further than Tuipulotu's team-mates at Scotstoun where two options present themselves, Stafford McDowall and Tom Jordan.

The former would seem the most obvious answer. McDowall has filled the role for Glasgow and Scotland with aplomb and was at 12 the weekend when he played for Warriors against Quins. It was a stuttering performance by Glasgow at the Stoop and things didn't quite click as we've come to expect but they did score a superb team try with McDowall at its heart.

It was the centre's first game back after a three-match suspension and it wasn't all plain sailing but McDowall has the benefit of playing regularly alongside Jones as well as the experience of last season’s Six Nations when he impressed in the final match against Ireland.

Jordan would be a more left-field choice. Selected as a stand-off, he is just as comfortable at centre and is versatile enough to play at full-back too, as he showed in the autumn. He may lack Tuipulotu’s creative flair but he is a combative presence and, again, links well with Jones.

The other centre options open to Townsend are Rory Hutchinson, the experienced Northampton Saints man who has been in and out of Scotland squads without nailing down a regular berth, and Matt Currie, the Edinburgh player who made his Scotland debut on the summer tour, played against Portugal in the autumn but is more suited to 13.

Cam Redpath, the Bath centre, is currently out with a leg injury. Townsend expects him to return midway through the tournament. Others outside the squad who could be considered are Sione’s younger brother Mosese Tuipulotu and his Edinburgh team-mate James Lang. Mosese was part of Scotland's autumn squad and played in the A game against Chile but recently lost his Edinburgh place to Lang who is not long back from injury.

The choices at second row within the squad now boil down to four names, two of whom are experienced and two of whom are not. With the 42-times capped Cummings unavailable, the obvious replacement to play alongside Grant Gilchrist (75 caps) is Jonny Gray (77 caps). The only snag being that both locks arrive on the back of recent injuries, Gilchrist's to his hand and Gray's to his ankle. Townsend will hope that both are fit and firing by February 1. The more callow second row choices are Glasgow’s Gregor Brown, who has four caps, and Edinburgh’s Marshall Sykes, who has one. Both have impressed this season and at least one looks set to be in the match-day 23 for the Italy game.

Other second-rowers who could force their way into consideration but are currently not part of the squad include Cam Henderson, Sam Skinner, Alex Samuel and Alex Craig. Max Williamson is, unfortunately, injured.

There is no escaping the fact that Tuipulotu and Cummings’ absence is a serious blow to Scotland’s chances. Injuries are a fact of professional sport but to lose your captain and talisman is terrible timing.

Tuipulotu should have been in Rome on Tuesday to represent Scotland at the official Guinness Six Nations launch. Unfortunately, he is one gladiator who will not be entering the arena this year.