Manchester United have had a lot to be proud of this season.
Despite finishing sixth in the Premier League, the Red Devils' campaign was salvaged by their triumphs in the EFL Cup and the Europa League.
That feelgood atmosphere has continued into the close season, with Old Trafford staging Michael Carrick's testimonial last weekend.
The likes of Paul Scholes, Ryan Giggs, and Edwin van der Sar were on show in a team reminiscent of the 2008 side that won the Champions League.
More observant staff at the Theatre of Dreams also noticed some frankly bizarre goings-on the evening before the game, and it has prompted a strong reaction from the club.
As seen in the video below, a group of teenagers decided to embark on a spot of Parkour, or free-running, inside the famous ground.
The youths scaled the roof and dangled over the edge, before taking a quick jog onto the pitch.
Check it out below - not for the faint-hearted:
It was there that it all came to an end as they had to make a quick escape after being spotted.
Unsurprisingly, this has not gone down well with United. As per the Daily Mail, the club have branded the individuals in the video "stupid and irresponsible".
United were unimpressed
The statement read:
"Their stupid and irresponsible actions, especially at such a sensitive time, put last Sunday's game at risk and occupied both club staff and, more importantly, police officers in hours of work to make sure that the stadium was safe to stage the match.
"The response of the police was outstanding. With over 130,000 people coming into the Old Trafford area on Sunday, the last thing they needed was to have their time wasted in this way. But as ever, they conducted a thorough search of the stadium to confirm it was safe to hold the match."
Strangely, this isn't the first time such an intrusion has happened at Old Trafford.
Last season, two fans managed to stay in the ground overnight after a stadium tour in the hope that they would see their side play Arsenal the following day. Or you know, just buy a ticket like most supporters do.
That attempt was also thwarted, but more questions are now going to be asked about the security measures in place at United.
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