Celtic manager Tony Mowbray pointed to defensive injuries after seeing his side lose two points in the SPL title race as they were held to a 4-4 draw at Aberdeen.
The Bhoys led 4-2 at Pittodrie with 15 minutes to play, but failed to hang on for victory and fell ten points behind league leaders Rangers as a result.
Mowbray said afterwards: "We have problems in defence, injuries to key players. If we had more options we might not have lost these goals.
"We tried to bring in a couple of defenders during the window and the fact we weren't able to do so wasn't for the want of trying.
"One part of the pitch is functioning reasonably well, but the other has some problems.
"We were 4-2 up but a game is never won until the final whistle. The performance wasn't very good and the result wasn't very good."