Wigan could face a fight to keep in-form forward Victor Moses after the player's agent indicated he has halted talks over a new deal.
The 21-year-old Nigeria international, who joined Latics in a £2.5million move from Crystal Palace two years ago, has just one more season remaining on his contract.
Wigan have been trying to discuss an extension since December but agent Tony Finnigan says Moses has now decided against it.
Finnigan told Press Association Sport: "An offer was made some months back - turned down - and we were still in negotiations.
"In the last week we spoke again and the player has now decided, 'I don't want to extend my contract'."
Wigan pulled off a coup to sign the highly-rated Moses from Palace and his performances since, particularly in the latter half of this season, have earned rave reviews.
The former England Under-21 winger has been inspirational over the past month as Latics have enjoyed a resurgence to pull clear of the Barclays Premier League relegation zone.
Roberto Martinez's side have spent most of the campaign in the bottom three but are now five points clear of danger after impressive wins over Liverpool, Manchester United and Arsenal in recent weeks.
Finnigan points out there is no animosity between Moses and the club but the player has simply decided not to renew.
He said: "It doesn't mean he doesn't like his manager - he chose Wigan over other clubs.
"Martinez is a tactical genius and an excellent coach, and they are Victor's words.
"He's been playing regularly, he's in form and enjoying his football.
"He has been offered the chance to extend his contract but has said, 'No thank you'."
Moses, who represented England at under-age levels but pledged his international future to the country of his birth earlier this year, could now be targeted by other clubs this summer.
Martinez has been delighted with Moses' recent form and spoke only this morning about how much he hopes the player can continue his development with Wigan.
The Spaniard, speaking at a press conference to preview Saturday's game at Fulham, said: "I always felt Victor Moses would one day fulfil his potential and when he does that he will be a top, top player.
"We are all delighted to have him developing as he is doing.
"All I want is Victor to be happy, to be able to develop.
"There is still a long way to go because his potential is huge but it is great to see a young man like him take responsibility and take a big role in our team and have a massive say in how to win games."
Martinez's own future has been the subject of speculation but the former Swansea boss last week rubbished reports he is set to quit the club at the end of the season.
With the wins over United and Arsenal having followed since the rumours surfaced, the team were clearly not unsettled by them and Martinez feels they may even have been inspired.
The 38-year-old, who resisted overtures from Aston Villa last summer, said: "It is a bit irritating at the start and you have to look a little bit deeper to see where the rumour is coming from. Probably you see it is part of the game we are involved in.
"But internally we couldn't be stronger - we have got a chairman who is a joy to work with, someone who inspires everyone at Wigan Athletic.
"There is no problem internally and nothing will affect that.
"From then on it becomes an incentive to make sure we get the results and carry on grabbing headlines for the right reasons."
Martinez rates both striker Hugo Rodallega and midfielder Shaun Maloney as "50-50" for Craven Cottage.
Rodallega has been out for six weeks with a knee injury while the in-form Maloney missed Monday's win at the Emirates Stadium with his own knee problem.
After recent results, Martinez must now control expectations ahead of the final four games of the season.
He said: "To have the mentality to go into these grounds and play against these sides with the eye-to-eye mentality, and being able to get the three points, is a fantastic achievement.
"Every player in this football club deserves huge credit.
"But we know we don't have enough points. We have 12 points to fight for and we need to make sure we keep the same approach."