The 36-year-old, who signed a new one-year contract earlier this summer, was hurt in a collision with goalkeeper Nikola Milojevic in Wednesday night's 1-1 draw with Vitoria de Setubal in Portugal.

It was initially hoped the former Sydney FC man had only suffered bruising, but he will now undergo X-rays with medical staff fearing the worst.

Manager Roy Keane told the club's official website, www.safc.com: "We thought it was just a bang on the head, but there could be a fracture there, around his eye.

"He will be out for a number of weeks."