Manchester United fans have been trying hard over the summer to make it crystal clear to the Glazer family that they’re not welcome at Old Trafford.

United fans were staunchly against the Glazer family’s takeover in 2005 and, 14 years later, the anger towards the Americans is as strong as ever.

The Red Devils have fallen way behind Europe’s elite in recent years and most supporters believe the Glazers are directly responsible for the club’s decline.

United fans started a ‘Glazers Out’ movement on social media in June, while a boycott of MUTV - the club’s official TV channel - followed several weeks later.

However, they have been left frustrated with the lack of support from former United players, including outspoken pundit Gary Neville.

The ex-United captain, who has set the benchmark for football punditry on TV in recent years, has - for one reason or another - been reluctant to speak out about the Glazers in his role on Sky Sports.

This has led to criticism from some United supporters who feel that Neville would significantly improve their chances of getting rid of the Glazers if he said he wanted them gone.

Neville, however, took offence to some fans calling him a ‘Glazer apologist’ and explained why it’s pointless campaigning for United’s owners to leave the club on social media.

“From muppets on here who think something trending or an ex player having a go will move the owners out of the club!” he tweeted on Sunday. “Owners don’t leave clubs unless they want to or are being hurt commercially. A bit of noise on here isn’t going to do a jot! It’s like a fly attacking an elephant!”

This sparked a response from Neville’s former United teammate John O’Kane, who was part of the famous Class of ’92 but only managed to make a handful of first-team appearances for the Red Devils.

“#GlazersOut fans are trying to create awareness of what the owners are doing to #MUFC simple,” he replied. “We know they won't sell, but to do nothing and let the owners ruin this great club is not on. Calling out a few ex players for "having a go" I couldn't give a f**k what you think of me.”

This led to a brutal response from Neville, who decided to get personal with O’Kane.

“Are their [sic] 2 John O’Kanes?” he tweeted.

“The one I knew that cowered at the thought of giving his all for the club and was unprofessional whilst wearing the shirt and this one who is a Twitter warrior and represents the fans with all his heart.

“Can’t be the same bloke surely!”

Wow.

That’s pretty savage, Gary.

O’Kane then said: “Some make it at Utd Gaz some don't we all have different paths I've found mine now! as football wasn't for me go f**k yourself.”

Neville simply replied with a laughing emoji.

However, his comments have not gone down well with many United fans on Twitter…