By Manchester correspondent Alex Stevens

Gary Neville has claimed that Louis van Gaal’s position would be under threat if he was managing Barcelona or Bayern Munich.

The Manchester United manager admitted on Friday that he has faced player unrest, with Wayne Rooney and Michael Carrick intervening to warn him about dressing room morale.

Pundit and England assistant coach Neville says the warning signs are starting to flash at Old Trafford.

‘I’ve always maintained that Manchester United should give their managers a minimum of two to two-and-a-half years, however messy things get,” Neville wrote in his Telegraph sport column. “My support for Louis van Gaal is unchanged but there are red flags on some of the things we’ve seen at the club.

“At the time he started to come under serious pressure I stuck by David Moyes, even though you could see all was not rosy. It’s quite clear that all is not rosy now, either, with the player tensions and the sometimes stagnant football, but I still believe United should stand by Van Gaal through this season and the start of next.”

Neville added: “He is at the point, though, where he has to start delivering the performances that go with the fantastic amount of money he has been given and the incredible support from the fans.

“Van Gaal is fortunate to be at a club with Manchester United’s traditions. If he were playing the football he’s playing and getting the results he’s getting, having spent the money he’s spent, at Bayern Munich or Barcelona, he would be in significant trouble. United take a longer-term view.”

However, the former England and United defender says he is concerned about Van Gaal’s man-management style and his apparent disregard for players’ feelings.

Neville wrote: “I have real concerns that Louis van Gaal has fallen out with numerous players over the last year. Some of those players he actually brought in himself. Angel di Maria and Victor Valdes would be examples.

“There seems to be an element of the iron fist with Van Gaal. For 25 years people talked of Sir Alex’s ‘hairdryer’ but Sir Alex had compassion, while Van Gaal tends to be colder in his dealings with players. It hardly bodes well when players are brought through the door by a manager who then discards or marginalises them.

“Di Maria, Valdes, Falcao, Rojo, Van Persie – and there are others. That’s too many players to get on the wrong side of. These are not bad lads. So I’m slightly concerned that there is this iron fist being applied to players who I look at from personal experience and think: they’re quite good people. I know some of those lads, and they are what I would classify as really good professionals.”

Neville said he was particularly concerned by United’s transfer activity under the Dutchman.

“I am still saddened that Danny Welbeck left. I am saddened that Adnan Januzaj has been allowed to leave on loan to Borussia Dortmund. It was an early red flag to me when Welbeck was sold for £16million, as I said at the time. Januzaj went from playing four or five games on the bounce to going out on loan in Europe.

The transfer activity concerns me most. That carousel approach. If you had said to me at the end of last season Manchester United would have a net spend of £30-40million – that they would sign Schweinsteiger, Schneiderlin, Depay, Darmian and Martial – I would have been pleased to see signings who were either young and full of potential or highly experienced, in the case of Schweinsteiger, who brings control in central midfield and support for Michael Carrick.

“I would have called that a really good transfer window for Manchester United in terms of moving up from fourth to second or third in the Premier League.

“If you then said De Gea would be left out, Falcao and Van Persie would leave, Di Maria and Rafael would leave, I would have taken a breath and felt less sure. It is as if defeat has been grabbed from the jaws of victory. The nonsense around Neymar, Sergio Ramos, Gareth Bale and Thomas Muller has pushed people over the edge into thinking: there is a lack of decorum here. United have always been proud of their conduct in the transfer market but that polished feeling has gone.”