Cliftonville striker Ruaidhri Donnelly is set to miss the Boxing Day derby against Crusaders at Seaview with suspected ligament damage.
He suffered the injury early in the second half of his side's 1-0 victory over Coleraine at Solitude on Saturday.
Donnelly, 27, landed awkwardly after challenging for a header with Bannsiders full-back Aaron Traynor and had to be stretchered off.
The striker has scored six league goals for the Reds this season.
Paddy McLaughlin's men go into Thursday's north Belfast derby in second place in the table after a Conor McMenamin goal gave them victory over Coleraine.
Crusaders, meanwhile, are one point behind Cliftonville in third place after a 1-1 draw against Irish Premiership leaders Linfield at Windsor Park.