In the noisy transfer window of this summer, much self-serving debate has been heard about whether it is always bad to make deals with direct domestic rivals.
"There, it happens without any problem."
Mourinho is right that in Serie A rivalries fierce in the grandstands are quickly put on ice in the boardroom. He is also right about the frequency.
AC Milan have taken the defender Mathias Silvestre on loan from Inter, a year after Antonio Cassano went the other way, 18 months after Milan transferred Sulley Muntari from Inter, two years after Andrea Pirlo left Milan, free, for Juventus.
Mourinho is wrong to say it happens without any problem. At San Siro last week, Milan fans hung up a banner, "Matri? No thanks", responding to news of Milan's pursuit of Juventus's Alex Matri. The clubs promptly sealed the €12 million (Dh58m) transfer.
Taking on a player a rival club is prepared to discard will always rankle with some supporters. In dismissing that sentiment, executives contribute to the idea that a sport driven by passionate partisanship is increasingly the domain of businessmen.
Matri may well advance his career at Milan, and boost them, but for many he will long be the man not quite good enough for Juve, for a club fans thought was the enemy.
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