Scotland have been hit by a triple whammy of injuries following the Ireland match on Saturday.
Back-row Ryan Wilson will play no further part in the 2019 Guinness Six Nations, while two of their major stars are injury worries.
In a statement this morning the SRU said: “The Glasgow Warriors forward sustained knee ligament damage in the national team’s round two defeat to Ireland at BT Murrayfield Stadium on Saturday and will return to the care of his club’s medical team.
“Both remain part of the Scotland squad and will be assessed by a specialist this week to inform their programme of rehabilitation.”
Gregor Townsend shouldered the responsibility for Scotland’s Six Nations defeat at home to Ireland on Saturday.
Defending Grand Slam champions Ireland, reeling from a shock loss to England in Dublin in their opener last week, prevailed 22-13 at Murrayfield to reignite their title hopes.
Townsend had seen his side pick off Italy 33-20 last time out, but the head coach admitted their failings in attack against Joe Schmidt’s men pointed to mistakes on his part.
“I’m so proud of the players with the way they played and the effort they put in,” he said.
“A game of rugby is a lot of things. It’s the defence battle, the contact battle, the kicking game which is so important. I thought with the pressure we put on Ireland’s kicks, we won those battles.
“But it was just that final piece, the execution off set-piece which has been really good, that fell off the jigsaw today, and that’s my fault.
“I’m the attack coach, and we weren’t able to get those two or three phases either to get in behind the defence or set up our attack shape.
“I’m frustrated we gifted them a try through our error but very happy with how we played in the first half. The second half our execution of our set-piece plays to get us into our game just didn’t happen.
“If we were able to replicate that first half after the break, then I think we’d be here with a win.”
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