Brendan Rodgers has admitted Alistair Johnston appears to have suffered a hamstring injury.
The right-back had to be taken off on a stretcher after an off-the-ball injury against Kairat Almaty in the Champions League.
Johnston looked to clutch at his right leg as he tracked back at Celtic Park.
The defender received treatment after around 33 minutes before being withdrawn as he was unable to continue.
Quizzed on Johnston's condition and whether he had the knowledge of a timeline for the injury layoff after the match on TNT Sports, Rodgers said: "I don't, but it looks like a hamstring, which is a shame because he started the season so well."
Asked for an update in his post-match press conference, he added: "I haven't spoken to the medical guys yet, but it looks like a hamstring injury, which is disappointing.
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"I will get more in the morning."
Johnston was spotted in the Celtic dugout with crutches in the second half after being forced off.
The injury comes at at a crucial period for Celtic with the Champions League play-off second leg against Almaty in Kazakhstan next week.
Celtic face Livingston this weekend before the second leg in the Champions League.
Brendan Rodgers' side take on Rangers on Sunday, August 31 in the first derby tie of the Scottish Premiership season.
