Wayne Rooney has admitted he is under greater scrutiny than ever before in his career after a testing start to the season but the Manchester United captain believes he can still play a major part under José Mourinho.

Rooney has scored once in five Premier League games for Mourinho so far – against Bournemouth on the opening day of the season – and has been criticised after a series of disappointing performances. The England captain played the whole match on Wednesday as United ended a run of three successive defeats with victory over Northampton Town in the EFL Cup but in an interview with the club’s in-house television channel on Thursdaynight he acknowledged that it had been a hard few weeks.

Asked to comment on the scrutiny that he has attracted in the media, Rooney replied: “I think I’ve had that my whole career – a little bit more of late, I think, but that’s football. I listen to my coaches and my team-mates, the people around me, and I don’t really listen to what a lot of people out there are saying because a lot of it is rubbish. I have to focus, work hard, of course, and I’ve done that throughout my career. I’ve worked hard and tried to do my best for the team.”

He added: “That’s football, I think. We don’t win in three games and, of course, everyone is going to talk about it. We had a bad week, a bad eight days where we’ve lost three games, and it’s important now we react well to that and come through that.”

United face the champions, Leicester City, on Saturday as they attempt to get their Premier League campaign back on track after successive defeats by Manchester City and Watford. Rooney is expected to feature at Old Trafford despite his travails this season and the 30-year-old hit back at suggestions that his days as a striker are numbered.

“I’ve done that [played in different positions] throughout my career,” he said. “I feel I can play in all positions but I think the manager has made it clear either I’ll play up front or in the No10 and that’s where he sees me playing. As I said before, it’s not just myself – the whole team is going in and working hard. We had a bad week but we’ve been working hard to put that right.”

After the victory at Northampton, Mourinho took umbrage with what he described as the “football Einsteins” who have “tried to delete 16 years of my career” following the recent disappointing results. But Rooney backed the Portuguese to turn things round sooner rather than later.

“I think he’s been brilliant since he’s come in,” he said. “Training has changed a lot. The training has been really good and it’s interesting to see how he prepares for games with tactics, how we approach games, and it’s been really good. I’m sure obviously we will come back and definitely be challenging this season.”

Rooney is also relishing the prospect of facing City again in the fourth round of the EFL Cup after the rivals were drawn together on Wednesday night.

“For me, I think it’s the perfect draw. With what happened in the league, it’s a chance for us to get revenge for that result,” he said. “It’s going to be a great atmosphere. I think City will have 7,000-8,000 fans here, which will obviously make it an even better atmosphere. I think a cup game against City at Old Trafford is the perfect draw for us.”