The 26-year-old was forced off just before half-time in his side’s Top 14 match against Toulouse after a collision with Lucas Touzin. Russell, who had earlier scored a try, did not return after the break.
Although details of the injury were scant last night, television commentators stated that Russell had undergone and failed a head injury assessment (HIA).
The shortest turnaround for any player after failing an HIA is six days which means that, in the best possible circumstances, Russell could only be confirmed fit to play on the morning of Saturday’s international against France – not a scenario that Scotland coach Gregor Townsend is likely to accept for any number of reasons.
What options does Townsend have?
Peter Horne put in a man-of-the-match display when Glasgow beat Cardiff on Saturday night and Adam Hastings has been part of the national squad throughout the Six Nations.
Townsend’s main problem is that he is struggling for centres, with Huw Jones missing the remainder of the tournament after injuring his knee against Ireland.
Saracens’ centre Duncan Taylor and Mark Bennett are both long-term injuries, and Townsend may have to field Hastings and Horne as a revamped 10/12 duo, with Sam Johnson at 13 - although Newcastle’s Chris Harris remains an option.
Nick Grigg impressed in Glasgow’s 38-34 victory over Cardiff and is another option for replacing Jones in the midfield. The New Zealand-born centre put in a strong defensive performance against the Welsh side and was singled out for praise by Warriors head coach Dave Rennie, who highlighted his involvement in Glasgow’s opening tries.
Townsend is already without his first-choice back row from last year in John Barclay, Hamish Watson and Ryan Wilson, as well as in-form forward Sam Skinner and key prop WP Nel.
Last week, he also lost full-back Stuart Hogg to an injury that may keep him out for the remainder of the tournament.
The news was better for Scotland lock Richie Gray yesterday. On duty for Toulouse against Racing, the Scot - in only his second game back after injury - looked more like his old self, although it seems unlikely that Townsend will add him to the national squad at the moment.