Neymar has scored just three goals in his last nine appearances - a barren run of form given his high standards Getty Images

Manchester United have been handed renewed hope of signing Barcelona forward Neymar after former forward Terry Gibson claimed the Brazil international was the most likely of the club's attacking trio to leave the Catalan giants. Delayed talks over a new contract and a dismal recent run of form have led to speculation regarding the 24-year-old's future, with senior figures at Old Trafford having long coveted the player.

The player's father has confirmed that the 20-time Premier League champions have previously attempted to lure him to English shores. Barca wish to see off interest in Neymar by tying him down to a fresh deal which would keep him at the club until 2021, and raising his release clause to €220m (£173.6m, $250.6m), according to Mundo Deportivo.

However, following a run of three goals in his last nine games during which time Barcelona's lead at the top of La Liga was blown away and the club were knocked out of the Champions League, Gibson believes Neymar remains vulnerable to being offloaded by the Nou Camp side. The ex-Bolton Wanderers and Manchester City scout believes that should the trio of Lionel Messi, Luis Suarez and Neymar be broken up this summer – then the latter is most likely to depart – potentially opening the door for United.

"If you asked me two months ago if Neymar would stay at Barcelona, I would have said there was no chance he would leave," Gibson told Sky Sports. "I'm beginning to wonder now whether there is a possibility if a club came in.

"We've heard the stories about the stadium and the impact this may have on the finances at Barcelona. If Barca had to sell one of Messi, Neymar or Suarez then I think it would be Neymar. Neymar is the best age to sell, he's 24 so he's got a long time left to play. You would do everything you could to keep Messi and Suarez so Neymar is the possibility.

"Luis Enrique is the perfect person in position to see how he's behaving, how hard he's working in training and how he's living his life. All those things will contribute to whether we see the 'MSN' kept together next season. I'm not saying that is going to be the case, but I am leaning towards it more now."

A move for Neymar would likely require United to smash their transfer record, set when signing Angel di Maria from Real Madrid for £59.7m in the summer of 2014. The Argentina international spent just 12 months in the English top flight before moving to Ligue 1 side Paris Saint Germain.

But United executive vice-chairman Ed Woodward may be forced to take a similar gamble in the upcoming transfer window, as he continues to come under pressure from the club's fans who are demanding a marquee addition. Bayern Munich's successful capture of Renato Sanches, a player regularly linked with the club, from Benfica is only likely to stir tensions ahead of the summer window.