Scotland captain Sione Tuipulotu has been ruled out of the Six Nations Championship after being hurt in training last week while lock Scott Cummings' participation is in doubt after he broke his arm at the weekend.
Tuipulotu took over as Scotland captain in November but will miss the tournament after sustaining a chest injury during a training session with Glasgow Warriors last week, a statement from Scottish Rugby said.
"Sione will undergo surgery this week and is expected to return to action before the end of the season," it added.
It puts in jeopardy the 27-year-old’s hopes of touring Australia, where he was born, with the British & Irish Lions in mid-year.
Rory Darge and Finn Russell have been named as co-captains for Scotland’s Six Nations campaign, which starts at Murrayfield against Italy on 1 February.
The pair led the side in four matches in the 2024 championship, while Russell was captain when they started the campaign with an away win over Wales in Cardiff.
Cummings sustained an arm fracture early on in Glasgow Warriors' defeat by Harlequins in the European Champions Cup on Saturday.
"He is also likely to miss the tournament and will undergo further review to determine when he will be fit to return," added Scottish Rugby.
Scotland coach Gregor Townsend, who named a 37-man squad for the tournament last week, plans no additions to the squad at this point, it added.
Watch Dragons v Munster in the URC on Saturday from 7.15pm on RTÉ2 and RTÉ Player; Watch Ulster v Zebre in the URC on Sunday from 5pm on RTÉ2 and RTÉ Player
