Fracture fear for Sutton
The Bhoys were 2-1 down and chasing the game when Sutton went up for an aerial challenge.
The former Blackburn man did not see team-mate Bobo Balde jumping for the ball also, and was hit in mid-air by the towering defender.
This challenge knocked Sutton off-balance and he landed heavily on his arm.
The utility man was stretchered off following a spell of treatment, and was immediately taken to hospital.
Early indications from the Celtic camp are that Sutton has suffered a fracture that could rule him out of the latter stages of the SPL season.
Bhoys boss Martin O`Neill said: "I don't think it's good news on Chris. I don't know at this minute how bad he is.
"He came down on his elbow and I'm not sure at this minute how bad it is, but we'll know more in the next few hours."
O`Neill also commented on the controversial offside decision that deprived Celtic of what appeared to be a perfectly good equaliser.
John Hartson seemed to time his run to perfection as Henrik Larsson played him through, but he was flagged for offside.
Commenting on the decision, O`Neill said: "I was very disappointed to find out that the goal was disallowed and he was a yard onside.
"That's a big decision. It wasn't as if it happened very quickly. Henrik was running with him and in these games you have got to get it right.
"I thought the linesman was at a better angle than I was and I thought Henrik had delivered it right. The one thing about John is he holds his position well.
"I came down the stairs and by the time I had got down it had been chalked off, so I was disappointed and you can imagine how the players felt."