Brendan Rodgers has admitted Nicolas Kuhn is carrying a slight injury issue.
The winger is included in the Celtic matchday squad against St Mirren but is only fit enough for a spot on the bench.
Kuhn only completed some light jogging this week before ramping up his intensity ahead of the weekend.
Rodgers told Sky Sports: "He hasn't trained all week. He has a slight issue with his back.
"He has done some gentle jogging and then increased his level yesterday.
"He wasn't fit enough to start the game, we feel but I'm sure at some point today he will make an impact."
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Rodgers added: "It's a great opportunity for Adam Idah.
"Kyogo hasn't trained either really apart from the latter part of the week.
"I felt this was a game - and you see the physicality of St Mirren's line-up - a good game for Adam to start in and get his legs going again.
"He is a little bit behind his team-mates in fitness but he will get that over the course of the next few weeks and give everything to the game."
CELTIC XI: Schmeichel, Johnston, Carter-Vickers, Scales, Taylor, McGregor, Bernardo, Hatate, Forrest, Maeda, Idah.
SUBS: Sinisalo, Palma, Kyogo, Kuhn, Yang, Holm, Ralston, Welsh, Turley.
ST MIRREN XI: Balcombe, Iacovitti, Taylor, O'Hara, Ayunga, Gogic, Rooney, Olusanya, Brown, Fraser, Phillips.
SUBS: Urminsky, Kenny, Bwomono, Tanser, Sutherland, Taylor, Smyth, Idowu, Mandron.
