Ole Gunnar Solskjaer is not sure where Ander Herrera's future lies and suggested the uncertainty may have impacted the Manchester United midfielder's fitness.

Press Association Sport understands that the 29-year-old was intending to stay at Old Trafford and sign a contract extension, only for a lack of communication to see the Spaniard plan to leave at the end of his deal.

Herrera is believed to have committed to Paris St Germain over another option, although Solskjaer's appointment brought up a renewed push from United to agree terms to keep him beyond the summer.

"He's been working really hard to get fit from his injury that he sustained against Liverpool," the Red Devils boss said.

"Then he came back, and he got a different one here in training because he's been really putting a lot of work in.

"And, unfortunately, that's come at a time where, as you say, there are contract talks but that's ongoing, so I can't really comment too much on how far they have come down the line and what he's deciding.

"Well, you have to ask him (if there is any chance of him staying). I don't know how they've been, the last few talks, but we've let him focus on his fitness as well.

"He loves to play and he's not very happy when he can't help his team-mates and he's always giving his all – it doesn't matter if he's got five years left of his contract or five weeks."

Herrera is ruled out of Saturday's Premier League clash against West Ham with a muscle complaint sustained shortly after recovering from a hamstring injury.

Solskjaer, rather surprisingly, suggested that those injury issues could have been contributed to by the uncertainly over his future.

"Maybe the future might have been worrying him and maybe that's part of the reason that he's injured," the United boss said. "Who knows?

"You're never happy when you don't win games, but it's been a period now where we've played some good teams," Solskjaer said.

"We had some good performances, but we haven't had the quality in front of goal and belief maybe in front of goal that we should have because against Wolverhampton and Arsenal, the two league games, two of the last three, we should have won with the amount of chances.

"So, we've been practising. As a striker I know how important that little belief is and trust in yourself, so we've been putting balls in goals."