Warriors lose Holmes
Holmes sustained the injury playing for Glasgow Warriors 'A' against Edinburgh Rugby 'A' a fortnight ago.
Meanwhile, fullbacks Peter Murchie and Glenn Bryce and backrower Jason Hill are all progressing well. Murchie is back doing modified training as he recovers from an elbow injury, while Bryce and Hill have started running following ankle injuries.
Hooker Fraser Brown (foot) has been running on an anti-gravity treadmill while he continues his rehab and lock Kieran Low (concussion) is back doing non-contact training and is progressing through the graduated return to play protocol.
Centre Richie Vernon is currently undergoing rehab for a shoulder knock picked up in the game against Northampton.
Glasgow Warriors head coach Gregor Townsend said: "We all feel for Tyrone (Holmes), who has had some bad luck with injuries during the past two seasons.
"He had started the season in good form and had been working hard in training.
"We're disappointed to lose him for the next few months, however we wish him all the best with his rehab."