How Roberto Mancini fell victim to Inter intrigues with Jose Mourinho

The motivations for victory will run deep tonight for Roberto Mancini against Jose Mourinho, the man who signed a three-year contract with Internazionale even before the future Manchester City manager had been fired by the Italian club in deeply acrimonious circumstances.

The fractious relationship between Mancini and Inter in the early months of 2008 led the Italian dramatically to announce that he would leave at the end of the season in the press conference immediately following the club's Champions League elimination to Liverpool at the last-16 stage on 11 March that year. Rumours have always abounded about why Mancini calmly announced his intended departure, at 11.15pm in the San Siro press room. One of the foremost theories is that the Italian and his club's proprietor, Massimo Moratti, had had a blazing argument about the apparent defeatism of Mancini's pre-match declaration that "if by any chance we go out, we must not turn it into a drama".

But biographer Luca Caioli suggests in a new book about Mancini, A Footballing Life, that the Italian may have known by then about Inter's overtures to Mourinho, who was out of work after his departure from Chelsea. Moratti certainly moved fast for the Portuguese, who is two years Mancini's senior, after Liverpool's triumph. Though Mancini immediately recanted on his decision to quit – "I hope that all those who live football will understand my outburst and the bitterness one feels at such delicate times… but it was my heart and feelings talking," he said – Mourinho had a verbal agreement with Moratti by the end of March and he signed his contract with the club on 26 May, 24 hours before Mancini was shown the door.

Caioli provides a detailed picture of Mancini's sacking, in which Moratti dined with two old friends before meeting the manager at his house on Milan's Via Serbelloni. It took 20 minutes to tell him Inter and Mancini had reached the end of the road, despite seven trophies in four years and three successive Serie A titles. Mourinho was presented as the new manager on 3 June.

It was the Inter press release outlining the reasons for Mancini's departure which proved most contentious. The final part of it referred to leaked transcripts of a series of phone calls between a number of Inter employees, including Mancini, and Domenico Brescia – a 55-year-old tailor who served time in prison for conspiracy to commit murder and had Mafia connections. There was nothing incriminating in any of Brescia's conversations with Mancini and, after a legal stand-off, a compensation package believed to have been worth €8m (£6.4m) was agreed for Mancini.