Manchester United face fresh concerns following their 2-0 defeat to Atletico Madrid, with Lisandro Martinez openly questioning the club’s recruitment strategy and squad-building efforts. United legend Wayne Rooney has warned that such public criticism could damage unity inside the dressing room.

Speaking to Amazon Prime after the defeat in Madrid, Martinez argued that the club’s problems cannot simply be blamed on the manager or the players. The Argentine defender called for greater accountability higher up the club, particularly over the lack of investment in strengthening the squad during the summer transfer window.

“I expect more investment. One hundred per cent. I expect more from our technical director. As players, we have a lot to do, but it is also important to build a strong squad that is ready for nights like this,” Martinez said.

With pressure mounting on manager Michael Carrick, Martinez also suggested that repeatedly changing managers would not solve United’s wider problems.

“You cannot keep changing managers. What about the other areas? It is easy to blame the manager or the players, but we also have to look at other areas,” he said.

Carrick was asked about Martinez’s comments but declined to address them directly, saying he had not seen the interview and therefore did not think it was the right time to comment. The United boss stressed that everyone at the club cares about the team, although people express that in different ways.

Rooney, however, believes Martinez’s comments could have a negative impact on the dressing room. The former United captain argued that publicly questioning the quality of teammates crosses a line.

“It is disrespectful to his teammates. He is basically saying his teammates are not good enough. The only person who has the right to say that is Bruno,” Rooney said, while acknowledging that such conversations can happen behind closed doors.

Rooney also referred to his own experience at United. In 2010, he publicly criticised the club before a confrontation with then-manager Sir Alex Ferguson. Rooney later admitted that his approach had been a mistake and apologised.

Former England striker Alan Shearer also suggested during commentary at the Metropolitano Stadium that Carrick was being treated somewhat unfairly amid United’s struggles.

The defeat added further pressure on United and Carrick. It was their third defeat in five European meetings with Atletico Madrid, with United still waiting for their first win against the Spanish side in those encounters. Carrick, who moved from interim boss to permanent manager, now faces increasing scrutiny as the team struggles for consistency.