Today's Times reports that Donnie damaged the knee at the start of the week when he fell awkwardly in training. The initial diagnosis is that he has a tear to the cartilage.
With keyhole surgery, there is still a chance that if the operation today is at the more straightforward end of the scale, he might be back in action by the start of next month and, as Hugh Campbell pointed out, having played every week this season for either Glasgow or Scotland, Donnie should benefit from a short break. If the tear is serious, it would be several weeks before he is back in action, leaving Scotland without the only specialist openside flanker available to him.
"Hopefully he will be back in time for the Six Nations, but it's going to be tight," said Hugh Campbell, the Glasgow coach, in today's Herald. "He should be all right in terms of match practice because he has played almost every game. If it is a torn cartilage then the recovery time is much faster than it used to be. He is the best open-side in Scotland at the moment, so it would be a big blow for Matt Williams (the Scotland coach) if he was out any longer."
Donnie is banned from Glasgow's next Celtic League match after picking up his third yellow card against Edinburgh, but Hugh believes he has an outside chance of facing league leaders Neath-Swansea Ospreys the week before the Six Nations starts.
Donnie's absence comes at at a time when Glasgow are welcoming back a number of player from injury with Kenny Logan, Andy Craig and Cammy Mather all returning to training this week and being available for the game tomorrow against Toulouse. Scott Barrow and Nathan Ross are also reported to be close to a return to action.
Lock, Andy Hall, will miss the Toulouse game with a dead leg.
This week's wet weather has prevented the team getting out on to a proper pitch — even today's final run-out before tomorrow's game will have to be on an artificial all-weather surface. Contingency plans are being put in place to move the match in case the Hughenden pitch is unplayable, with Murrayfield the most likely alternative, though the club will do everything possible to make sure it goes ahead at their own ground.