Australian midfielder Tom Rogic has been ruled out of Celtic's Europa League meeting with Zenit St Petersburg on Thursday.
Rogic has been sidelined since mid-December because of a knee problem but was an unused substitute for Saturday's Scottish Cup win over Partick Thistle.
"He's going to be hopefully available in a week or so," said assistant manager Chris Davies. "He's had some good training and he's on his way back from being out for a while."
Patrick Roberts, Stuart Armstrong, Jonny Hayes, Craig Gordon and Marvin Compper will also sit out the last-32 first leg encounter.
Zenit have been without a league game since December because of Russian football's winter break but they warmed up for the Celtic match with a 3-1 win over Maribor in a friendly in Antayla.
Zenit are managed by the former Manchester City boss Roberto Mancini who guided his side to the last 32 by finishing top of a Europa League qualifying group that also contained Real Sociedad, Rosenborg and Vardar of Macedonia.
His side are second, eight points behind Lokomotiv Moscow a in their domestic league.
Celtic are 17/10 to win Thursday's first leg and 1/1 to qualify for the last 16 of the Europa League.
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