Sir Alex Ferguson's view on Mancini and letter sent by 'wildcard' Man Utd target

Roberto Mancini shares mutual respect with Sir Alex Ferguson and sent his former Manchester derby rival a classy letter upon his retirement.

The Italy manager, 57, has emerged as a surprise 'wildcard' contender to become the next permanent Manchester United boss at the end of the season despite his previous spell with local rivals Manchester City.

Mancini was in charge of City for three-and-a-half seasons between 2009 and 2013, famously pipping United to the Premier League title with a breathtaking final-day victory over Queens Park Rangers in 2011.

He also led the Sky Blues to an extraordinary 6-1 victory at Old Trafford to leave Ferguson stunned.

Mancini helped City overturn United's dominance and laid the foundations for current manager Pep Guardiola to develop the club into a European heavyweight.

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Although he was in the opposite dugout to Ferguson for many a fierce derby, he ensured he paid tribute to the legendary Scot ahead of his retirement at the end of the 2012/13 season.

"Yeah, I sent a message. I sent a letter," Mancini said of his correspondence with Ferguson in May 2013. "It is private and confidential."

He added: "Everyone can have his opinion but one manager who stays for 27 years in the same club and won every trophy for 27 years is an incredible situation.

"I don't think there will be another manager like him.

"In Europe, there are other good managers. I don't know if you can say Sir Alex is the best but he is the best in the last 27 years."

Mancini was speaking just days before he was sacked following City's FA Cup final defeat by Wigan Athletic.

Ferguson's respect for his counterpart was clear to see when he publicly criticised Etihad chiefs for dismissing their manager.

"It was quite amazing," said Ferguson of Mancini's sacking. "He has won the FA Cup, been in the final, second in the league and won the league and it's not good enough?

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"I was surprised, but actually no, you can't say you are surprised not with some owners today. You can't be surprised, but I still don't think it was right."

Ferguson also threw his weight behind Mancini when he was involved in a high-profile bust-up with City striker Carlos Tevez, who refused to come off the bench against Bayern Munich in the Champions League.

"I have nothing to do with it, but I think Roberto Mancini has come out showing his strength of character, his strength of management," Ferguson said of the incident.