Manchester United manager Jose Mourinho has admitted that he is "worried" over midfielder Marouane Fellaini's contract situation at the club.
Fellaini, 29, is in the final 12 months of his Old Trafford contract and will be free to speak to other clubs from January.
Left-back Luke Shaw is also in the final year of his contract at the club, but Mourinho said he was more concerned about the future of Belgium international Fellaini.
The 29-year-old, who joined United from Everton for £27.5m ($36m) in 2013, has established himself as a key player at Old Trafford under Mourinho.
"I'm worried about Fellaini and not about Luke Shaw because Fellaini finishes his contract and Luke Shaw doesn't," Mourinho was quoted as saying by Sky Sports.
Fellaini started 18 Premier League games for United last season, scoring one goal. He played the full 90 minutes of the club's win over Ajax in the Europa League final.
Galatasaray were linked with a move for Fellaini during the summer transfer window but Mourinho laughed off the rumours, saying that the Turkish club had more chance of appointing him as manager.
"Marouane is just the fact I think he has important qualities and I try to use these qualities depending on the situation, depending on the team's needs," Mourinho was quoted as saying by the Daily Mirror in September.
"He's a team player, a great character, we have a good relation and things are going really well between us.
"I think only a strong character would resist the difficulties here because he had some difficult times where people didn't recognise his qualities, where probably other managers didn't like so much the qualities that he has, so you have to be a strong character.
"He's a fighter, a guy with lots of pride. I'm really pleased I helped him to reach this and to change the perception the fans have now. I'm really happy for him."