Manchester United are believed to have trebled the amount of security at their training ground after supporters stormed the Carrington complex last week.
Red Devils fans are furious with the club's owners, the Glazer family, following their ultimately unsuccessful attempt to join the failed European Super League.
On Thursday morning a number of protesters turned up at training holding anti-Glazer banners and had to be calmed down by the likes of Ole Gunnar Solskjaer and Michael Carrick before they eventually left.
According to the Daily Mail United staff were shocked by the ease at which those present were able to breach security at Carrington, and as a result the club have acted in bringing in more security guards, as well as increasing the protection of senior executives.
Protests also took place before United's game against Leeds at Elland Road on Sunday, with a plane flying a banner over the ground with the message: "2bn stolen #Glazers out".
And there are expected to be further demonstrations at Old Trafford this weekend when United host bitter rivals Liverpool on Sunday.
Solskjaer recently called for unity in the wake of the disruption off the pitch, but insisted his players have not been affected by the chaotic scenes.
"The players are professionals and they’re very good at playing football," he said. "That’s what the focus has to be on, play as well as we can and get the supporters on our side.
"I think the owners of every club that signed up for this proposal have got a job on their hands, of course they have. We’ve had an apology from Joel and I think that’s important.
"He’s told us how committed he is to helping us going forward. Unity and everyone coming together and working together for one common goal is the best way forward.
“I’ve had an open and good relationship with them (the Glazers) and they’ve been very supportive of me, they’ve backed me."
