The current Italy coach led City between 2009 and 2013, and secured the club’s first league title for 44 years during his time in England.
However, he revealed one regret from his spell in the Premier League, when Giallorossi captain De Rossi left him in a rage after pulling out of a move to Eastlands.
“We spent one whole night in Rome talking,” Mancini told Il Messaggero.
“It was all done, but he pulled out at the last minute. He called me and told me: ‘I can’t go through with it.’
“I was hurt and angry. It happened such a long time ago, when Daniele was in the middle of his career.
“He would have enjoyed himself. I considered him to be a crucial player.”
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