Mourinho revealed this about the Chilean after he picked up a hamstring injury during training.

Things have just gone from bad to worse for Alexis Sanchez, as the attacker looks set for a spell on the sidelines. This is as confirmed by Jose Mourinho, revealing the player's injury ahead of a busy schedule.

The Red Devils are due to play eight games in the month of December alone. Everything begins on Saturday when they travel to Southampton before they host Arsenal at Old Trafford. However, the Chilean ace will not be available to face his former club.

According to the Special One, the South American forward has picked up an "important injury" and will likely miss the entire month of December. Mourinho was not going by a scan or an official medical report but spoke from experience about the player's hamstring injury, thus predicting he will be out for the remainder of this year.

"The first thing I can say is that in every club when a player is not playing it is a simple manager's decision," Jose said (via Goal). 

"In our club when a player does not play it is always because of the player is not behaving and has disciplinary issues. Of course, that is not the case again.

"He has an important injury, I don't want to risk by saying for how long he will be out but from the top of my experience, I would say he is not playing this year.

"No scans yet. But the player is experienced, the player knows what the injury is and also from the top of my experience, just the painful scream and the way the injury happened I know it's going to be for a long time.

"It's not a little muscular injury that in one week or 10 days the player is ready, is for me and also for Alexis, the feelings before the scans is that the grade is different than the Lindelof one and the Lindelof one was not an easy one, so I think Alexis has what I used to call an aggressive muscular injury."

If Mourinho's prediction turns out to be true, the clash with the Gunners will not be the only crucial tie Alexis will miss. On the 16th, the 20-time Premier League champion will be making the trip to Anfield for a tough encounter with Liverpool, but the Chilean might play no part in that tie.

The former Arsenal man will miss out on opportunities to fight his way back into Mourinho's lineup, having made only seven starts this season. Once one of the league's best attackers, Sanchez is now struggling with form at Old Trafford and has thus been linked with a transfer.

Rumors claim the Chilean favors a move to PSG. However, the English top-flight's highest-paid player must impress the Paris side before convincing them to meet his demands. This injury could thus set back a January move, had the player planned on packing his bags and leaving in the winter.