Wes Brown has revealed Manchester United team-mate Rio Ferdinand has been struggling with his back injury for some time.
Ferdinand has missed United's last two games as he struggles to shake off a series of niggling injuries.
The England star now looks certain to miss this weekend's showdown with Chelsea, live on Sky Sports 1 & HD1 as well as England's friendly with Brazil on 14th November.
Brown, who has earned a run in the side due to injuries to Ferdinand and Nemanja Vidic, admits Ferdinand has been playing through the pain barrier for a while and that the defender is now trying to resolve the problem.
"Rio has been injured for a very long time and he's been getting a lot of pain in his back for a long time," said Brown. "I'm not sure how many months it's been going on, but he's come to the stage where he's sorting it out now.
"When he comes back, I'm sure he'll be a lot stronger. If you are not fully fit and you try to play, it's very hard, especially with how fast the Premier League is now.
"If you carry on playing with that same injury, week in, week out, it does make things even harder. That's what happens and Rio has decided to sort it out."