Sky Sports understands Rangers captain Steven Davis will miss the rest of the season after undergoing a hernia operation.
Davis missed last weekend's win over Hearts with the problem and Rangers have now decided to send the midfielder under the knife.
It could mean Davis has played his last game for the Ibrox outfit with the club facing a fight to keep hold the 27-year-old this summer due to their dire financial problems.
Sky Sports understands Davis has a release clause of just £1.5million in his contract and the news is sure to alert a number of Premier League clubs who are thought to be waiting in the wings to sign him this summer.
Davis, who has been nominated for the the PFA Player of the Year award, has established himself as a key player since arriving from Fulham in 2008.
The Northern Ireland international was one of the players who agreed to take a 75 per cent wage cut last month in order to avoid substantial job losses at Rangers following their move into administration.