Manchester United forward Zlatan Ibrahimovic has been ruled out of the club's Champions League clash with CSKA Moscow.

After playing 59 minutes across four substitute appearances since recovering from a serious knee injury, Ibrahimovic had appeared to be in contention to start in the European encounter at Old Trafford.

However, boss Jose Mourinho has revealed that the Swede will instead do extra work in the gym in a bid to strengthen the area around his knee ahead of the upcoming Christmas period.

The 54-year-old told reporters: "Zlatan needs sometimes very hard work on the muscular area that supports the knee that had the problem, and when the period for that hard work comes, also the fatigue comes.

"He was on this cycle of work, divided between the gym and the pitch, and he will be out again for tomorrow but I believe back to normal work after CSKA."

United will top Group A providing that they avoid a heavy defeat to their Russian opponents on Tuesday night.