Wayne Rooney has warned that Manchester United are already in crisis after manager Ruben Amorim’s damning remarks in the wake of the club’s shock League Cup exit to fourth-tier Grimsby Town.

United crashed out of the competition on Wednesday after a dramatic 12-11 penalty shootout defeat, with summer signing Bryan Mbeumo striking the crossbar in the decisive moment. Amorim, visibly distraught, admitted afterwards: “I felt my players spoke really loudly today what they want.”

Reacting on The Wayne Rooney Show on BBC, United’s all-time record goalscorer said the comments pointed to deep problems inside the dressing room.

“Just the way they lost, it was disheartening. There’s something not right,” Rooney said. “The manager’s words after the game were damning on the players. Having been in that dressing room myself, if your manager says that publicly, it means something is broken.”

United finished 15th in the Premier League last season, their worst position since 1974, but expectations had been high this term after a full pre-season under Amorim and more than £200 million spent on new attacking talent.

Instead, the Portuguese coach has overseen a shaky start a home defeat to Arsenal, a draw at Fulham, and now humiliation against Grimsby sparking questions over his future just three games into the campaign.

Rooney, who suggested Amorim may be overwhelmed by the magnitude of managing United, said the job was unlike anything he had previously experienced.

“He’s 40, he’s still a young manager, and Manchester United is so different from Sporting Lisbon,” Rooney explained. “There’s the media, the commercial pressure, the fans it’s on another level. And when you’re not winning games, it gets to you. It looks like he’s reached a breaking point.”

Amorim was appointed in November after Erik ten Hag’s dismissal, but Rooney believes the early signs suggest he may struggle to withstand the scrutiny that comes with leading one of the world’s biggest clubs.