Rangers will be without Danny Wilson for Saturday's Scottish Premiership clash at home to Hearts, live on Sky Sports 2 HD from 12pm.
The defender limped off against Partick Thistle last Sunday with a knee injury and has been ruled out for the season.
Wilson will meet with a specialist next week to determine how long his rehabilitation will take.
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The news is the latest in a long line of injury concerns for Rangers who have lost on-loan midfielders Emerson Hyndman and Jon Toral, both of whom have already returned to their parent clubs Bournemouth and Arsenal respectively with knocks.
Other absentees are Lee Hodson, Philippe Senderos and Niko Kranjcar who all have knee injuries, while Rob Kiernan and Jordan Rossiter have calf issues, and Lee Wallace has a stomach problem.
All of which could mean teenager Jamie Barjonas makes another appearance, following his debut at Firhill last weekend.
Meanwhile, Hearts defenders Andraz Struna and Lennard Sowah will miss the trip to Ibrox.
Neither full-back has fully recovered from the muscle injuries which forced them off the field against Aberdeen last weekend.
John Souttar and Callum Paterson remain on the sidelines with Achilles and knee concerns respectively.