Inverness Caledonian Thistle midfielder Lee Cox is facing several weeks more on the sidelines and has been sent to a specialist because of a groin problem.
Cox missed Saturday's opening game of the season as Terry Butcher's side lost 3-0 to Motherwell.
And the manager told his club website: "Lee's not been making progress.
"Sadly, it looks like he'll not just miss Saturday's home game with Hibs but be sidelined for a few weeks yet. It's a real pity for us and the lad."
However, Butcher hopes to have new signing Thomas Piermayr registered in time to face Hibernian this weekend.
The 21-year-old former Linz defender, an Austria Under-21 international, was signed too late to feature at Fir Park.
Piermayr, who played for Kilmarnock in a pre-season friendly with Ross County, turned out for Caley Thistle away to Buckie Thistle last week.
"Thomas has good pace, a lovely touch and is hungry to succeed," said Butcher.
"He's versatile and can play right-back, left-back or midfield.
"He's got good Austrian League and under-21 international experience."
Butcher is also hoping to add one or two more signings before Saturday.
"Our resources were stretched for the Fir Park game, but we hope to have one or two back for Saturday, plus one or two new faces, including Piermayr.
"We are pursuing a range of enquiries."