The BBC has learned ex-Chelsea boss Mourinho, 53, could replace Louis van Gaal as United manager this summer.

McCarthy, 38, played under Mourinho during the Portuguese's time at Porto.

"Mourinho is one of those people who knows how to beat Guardiola's tactics," he told BBC Sport.

"When he was at Real Madrid, he beat him a couple of times. At Inter Milan, he also had success against him.

"At the moment, I can't see anyone taking on Pep and his tactics at Manchester City but with Mourinho at United, he would have the resources, the players and the financial backing to beat Guardiola."

Former Barcelona coach Guardiola, now in charge of Bayern Munich, will succeed Manuel Pellegrini as City manager in the summer.

Mourinho's second spell as Chelsea boss ended in December, when he was sacked after losing nine of the season's first 16 league games.

His departure came just seven months after he had won his third Premier League title with the Blues, the first two of which came during his first spell at the club - from 2004-2007.

Mourinho fell out with the Blues' medical team, in particular club doctor Eva Carneiro, after describing them as "naive" for running on to the pitch to treat midfielder Eden Hazard during a draw against Swansea in August.

McCarthy, who won consecutive Portuguese titles and the Champions League at Porto, said suggestions his former boss is "damaged goods" are "majorly unfair".

The South African added: "Everywhere he has gone, he has been successful.

"The fans, the media, the people don't know what went on behind closed doors at Chelsea and what caused the problems they had when he was in charge. I certainly don't think that experience makes him a bad manager.

"The problems he has had of late seem to be due to personality clashes. When you want more from your players and they think they can't give you more, it results in a clash and players don't play to the best of their ability."

McCarthy said Mourinho's man-management skills were "unbelievable".

He added: "Manchester United have a lot of young players, who want to achieve things and make names for themselves. He would come in and be the perfect man for the job.

"If the players give him 100% effort, and show a willingness to succeed, he could definitely get Manchester United back to being one of those powerhouses in Europe, where teams fear to go."

'Mourinho ready for a long-term jMourinho has never spent more than three years in a single spell as manager of a club.

But McCarthy feels he is ready for a long-term challenge, and thinks United would be the perfect job for him.

"During my time at Porto he had time to settle in and instil his philosophy," said McCarthy. "Nobody interfered much in what he was doing. He had full support and I think that is why he was so successful.

"Manchester United is that kind of club. It is a very well-run club and a family club. Because of that I think he will be able to make those players play to their ability and put the club back where they belong.

"I definitely think he wants that opportunity to have a long-term spell at a club, where he can build a foundation and fix things properly. When he gets that, people will see the real Mourinho we all know."

Van Gaal has responded angrily to speculation about his job, and said there was no need for the club to deny they were in talks with Mourinho.

But both he and predecessor David Moyes, who was sacked just 10 months after succeeding the legendary Sir Alex Ferguson, have struggled to match expectations at Old Trafford.

McCarthy said Mourinho wants the challenge of "following in Ferguson's footsteps" so he is not just known as "someone for a short-term fix".

He added: "He is not quite up there yet with Ferguson but, in terms of what he has won, he is only one of a handful of people who can take the Manchester United job and rebuild it.

"It is the people's club and he would have the right resources to once again make them one of the most fierce teams in Europe. He would come in, change things around and get one up on Chelsea."

(BBC)