Shaun Maloney and Scott Brown are fit again after recovering from tendinitis and an ankle operation respectively but will not join in with full training until Monday.
However, McInnes, whose side lost 5-2 at Parkhead earlier in the season, believes whoever wears the hoops will be more than capable.
"I don't take any comfort from the fact that Celtic will be without a few players," he said. "Not at all.
"I understand there will be a few changes but whoever comes in to play for Celtic will be quality.
"The size of club they are means they will have a strong team.
"In fact, Celtic are the most impressive side we have played this season.
"We lost 5-2 at Parkhead and that day they had a lot of match-winners on show.
"They had Brown, Maloney and McGeady in the midfield and Fortune and McDonald up front.
"They had the ability to pass and move the ball, they were athletic and had lots of energy.
"But although we lost against them, we took a lot of positives ourselves and in some ways we were the architects of our own downfall.
"We have to defend better to give ourselves a platform and and if we do that, who knows?"
McInnes paid tribute to Saints goalkeeper and club record appearance holder Alan Main who has been granted a testimonial.
The keeper, who has clocked up 361 starts for the club in two spells at Perth, is being honoured by Saints fans, with plans coming together for a variety of events
McInnes said: "I have nothing but admiration for Alan. He is a huge credit to himself and I am delighted for him.
"I played with him and as a manager, I saw how hard he worked last season to get another chance to play in the SPL.
"He's a popular guy, I'm sure St Johnstone fans will turn out to honour him."
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