Back row Luke Crosbie (26) and lock Richie Gray (34) will miss the rest of Scotland's Six Nations campaign after sustaining injuries in their opening win over Wales, Scottish Rugby said on Tuesday.
Crosbie suffered a shoulder injury and Gray is ruled out with a bicep issue.
Scotland claimed a dramatic first win in Cardiff for 22 years after withstanding a remarkable fightback from Wales to seal a 27-26 victory on Saturday.
Winger Darcy Graham and prop WP Nel are recovering well from their injuries and will both resume training with Edinburgh this week, Scottish Rugby's statement added.
Scotland face France in their second game on Saturday.
