Barry Ferguson believes Celtic took a gamble allowing Leigh Griffiths to leave and they might regret it due to their striking problems.
Kyogo Furuhashi is out injured, Odsonne Edouard departed for Crystal Palace and new signing Giorgos Giakoumakis isn't fit enough to start.
Ange Postecoglou started Albian Ajeti in the disappointing defeat against Livingston on Sunday just hours after Griffiths completed ninety minutes in the Dundee derby.
Rangers legend Ferguson admits Griffiths was correct to join Dundee on-loan in search of regular football but the Alloa boss insists Celtic need fit players.
He said: "Was I surprised that Celtic let him go? I don't think he was going to get a chance there.
"Leigh Griffiths has got to think about himself and that's by playing games of football.
"But Celtic are thin up top. Did they expect Kyogo to get injured on international duty? No, they didn't. But that's the gamble you take.
"You sign a striker who's not fit, the Greek guy. He's not fit.
"You're at Celtic here - you need players!"
"I watched the Dundee Derby, he (Griffiths) had a great header just by the post, then he had another chance where the keeper makes a good save.
"Naturally he tires as the game goes on because he's hardly played a game of football."
Gordon Strachan was spotted at the televised Dundee derby in his role as technical director at Dens Park.
The former Scotland boss is also working at Celtic in a consultancy role at Ferguson questioned his dual employment.
He said: "It's strange, it pans around to the stand and Gordon Strachan is there with his Dundee tie on.
"He's employed by Dundee, he's employed by Celtic for the next three months.
"I do find it strange. Things like that in football – I don't understand it."
