Glasgow, Scotland (SportsNetwork.com) - Celtic defender Mikael Lustig is facing a lengthy spell on the sidelines after undergoing hip surgery this week.

The Sweden international is expected to miss the next four months with the injury after manager Neil Lennon revealed that he had been playing through the pain for some time.

"Lustig had surgery, (and will be out for) four months," Lennon said. "He had both hips done, so the procedure was a bit more in depth than first thought.

"We are hoping he will be back March/April time but he had a lot of work done which makes his recent performances even more remarkable."

The 27-year-old featured 26 times in all competitions for the Hoops this term with the team sitting seven points clear at the top of the Scottish Premier League.