Furious Manchester United fans protesting against the Glazers family's ownership blocked both entrances to the club's Carrington training ground on Thursday morning in the wake of the European Super League scandal, Sky Sports reported.
Joel Glazer, unveiled as European Super League vice-chairman when the bombshell announcement was made on Sunday, apologised on Wednesday in an open letter to all United fans after the club pulled out of the plans the day before.
Around 20 fans blocked the entrance to the training ground before entering and posing with banners which read: 'We decide when you play', 'Glazers out' and '51% MUFC 20'.
"At approximately 9 am this morning, a group gained access to the club training ground," read a United statement on Thursday.
"The manager and others spoke to them. Buildings were secure and the group has now left the site."
Around 20 protestors accessed Carrington, carrying banners, and made their way to reception and to the first-team training area. Police were called to the training ground.
The fans entered the club's training ground before the majority of the first team had arrived and blocked both entrances as they stood with their banners. The '51%' banner is in reference to fans holding the majority of voting rights at the club, a model which is common in German football.
The protestors made their way into the training ground to the first-team pitches where they posed for pictures with their banners and demanded to speak to Solskjaer.
It is understood that the Norwegian did come out to speak to the supporters, along with technical director Darren Fletcher, first-team coach Michael Carrick and midfielder Nemanja Matic.
The group left shortly after and while the police were called it is understood no arrests were made.
The Red Issue Twitter account showed an image of fans on a training pitch with a banner reading 'Glazers Out' and another saying '51% MUFC 20' in reference to the model of ownership used widely in Germany.
Manchester United fans have been annoyed with the ownership of the club since the Glazer family takeover in 2005, with there having been numerous protests since then.
The basis of their anger is around the debt that was brought in to the club and many fans believe the American owners do not have United's best interests at heart.
And the protests gained momentum once again following the announcement of the Super League on Sunday, with fans having been left frustrated at a lack of communication.
Chelsea supporters were seen gathering outside Stamford Bridge on Tuesday night, with Liverpool fans having staged their own protests at Elland Road on Monday evening.
With United not having a game until Sunday, away to Leeds United, fans decided on a different course of action by heading to Carrington.
A statement from Manchester United Supporters' Trust said the proposal to form a breakaway league with 11 other clubs was a "betrayal of everything the club had ever stood for".
They added: "A Super League based on a closed shop of self-selected wealthy clubs goes against everything football, and Manchester United, should stand for."
The reaction from fans, players, managers and official organisations led to United making the decision to withdraw from the proposed new competition and Joel Glazer penned an open letter to fans to admit they made a mistake with their decision to form the league.