Celtic's injury problems mounted on Thursday when striker Chris Sutton became the latest player to join the Scottish champions' extensive list of absentees.
The former Blackburn Rovers and Chelsea player strained a chest muscle and was forced off as Aberdeen ended Celtic's unbeaten Premier League record on Wednesday with a 3-2 win at Parkhead.
A scan on Thursday confirmed Sutton's injury and the Glasgow club expect him to be missing for a "few weeks" ruling him out of home matches with Motherwell in the league on Saturday and Tuesday's Champions League Group F clash with Shakhtar Donetsk.
Sutton, a key player for Celtic over the past four years, could also be ruled out of the Old Firm games with city rivals Rangers at Ibrox in the League Cup quarter-finals on November 10 and in the league 10 days later.
Manager Martin O'Neill, who has described his squad as "threadbare", said: "We're obviously very disappointed as this is a big blow but it's one we'll all simply have to recover from."
Alan Thompson, Henri Camara, Stephen McManus, Joos Valgaeren, John Kennedy, Shaun Maloney, Ulrik Laursen and David Fernandez all missed the Aberdeen match due to injury.
That home defeat and Rangers' 2-1 win at Dunfermline Athletic the same night has cut Celtic's lead at the top of the standings to four points after 11 matches.