Steven Gerrard admits Ryan Jack is facing a race against time to be fit for Rangers' Boxing Day game against Hibernian.
The midfielder was rewarded for his impressive form with a new contract on Friday but then sat out Sunday's win at St Johnstone with a groin complaint.
Rangers face two crucial clashes ahead of the new year as they square up to Hibs and then Celtic, but Gerrard fears his injury list will not clear in time.
The boss, who is also sweating on the fitness of Scott Arfield, Gareth McAuley, Borna Barisic and Ryan Kent, said after his side's 2-1 win in Perth: "We need a 90-minute performance for the next two games now. That's an understatement.
"Hopefully we can add one or two bodies to the group. You could see today quite clearly that we're having to dig deep and use our squad.
"I can't confirm that anyone will be back for the next game just yet. But hopefully in the coming days we get a breakthrough in one or two.
"Ryan Jack had a small issue in his groin. We're hoping he is fit for Hibs but I can't confirm that just yet."
Gerrard was forced to turn to former skipper Lee Wallace when Barisic limped off against Saints.
It was only the left-back's second appearance since September last year and his boss said: "You could see that he hadn't played for that amount of time. He did OK, defended well at times.
"But it will take him time to get back to his best, although he did communicate and was trying to lead.
"I'm pleased for him that he's come back in and sampled a win, because he's been working hard in training. And he deserved his opportunity to today.
"But I think it's unfair to judge Lee Wallace's performance today with a microscope, because he's been out for so long."
