John Kennedy admits he doesn't know if James Forrest will be fit to face Rangers in the Scottish Cup at Ibrox next Saturday.
The winger, just back from six months out with an ankle injury, was taken off in yesterday's 6-0 win over Livingston at Parkhead.
Forrest, who had opened the scoring for the Hoops, was replaced as a precaution and gaffer Kennedy says he'll be monitored in the build-up to next week's Old Firm clash.
He said: "We are not quite sure yet on James. He stiffened up around his back and hamstring so it was a case of not taking any risk with him.
"The scoreline allowed us to do that and give other boys game time.
"It's too early to say about James for next week, we'll have to assess him.
"When it's general stiffness around the hamstrings, you usually concern yourself but hopefully we got him off quick enough.
"It's a different area (from the ankle) and with players coming back after so long out, you do get niggles which are hopefully a day or two in passing.
"But I don't want to say too much."
Stand-in boss Kennedy was delighted with Celtic's performance against Livi, with goals from Forrest, David Turnbull, Ryan Christie, Moi Elyounoussi and a Jack Fitzwater OG.
Kennedy believes they can trouble Rangers next weekend - notwithstanding an SFA statement on Saturday afternoon that could throw the date or time of the clash in doubt as it now clashes directly with the funeral of Prince Philip.
He said: "The performance gives us the foundation to get results. It's been a case of building the structure, make sure everyone knows their role - and then the quality comes through.
"If you get the basics right you can control games and build up confidence. Today, our important players did damage in the opposition box.
"It was really pleasing because I thought our decision making in the final third was very good as well. It was a top performance.
"We know if we're on our A-game we can cause Rangers huge problems.
"So it was good to come out of a game scoring goals and having that extra bit of confidence.
"Hopefully we can take that into next week.
"Do we have something to prove against Rangers? There always is.
"Last time, we did in terms of performance but now it's all about getting a result next week.
"I've felt this coming for a few weeks, as if we were going to give someone a bit of a hiding and today was a great example of that. We put it all together in terms of performance."
