Mancini was in the stands on Sunday to watch the 19-year-old in Serie A action.
He impressed during a run-out against Roma, netting Sampdoria's third goal in a 3-1 win, and sent Mancini back to England mulling over a possible summer approach.
It was suggested that the City manager was actually in Italy to cast an eye over Roma's Brazilian full-back Marquinhos, who is also believed to be attracting interest from Barcelona.
It was, however, Icardi who made a lasting impression on the Blues boss.
The Argentina U20 international was the subject of a sizeable bid from Napoli during the winter transfer window, while Inter Milan are said to be keen on putting a summer deal in place.
Icardi could soon be on his way to England, though, with few sides capable of competing with City's spending power in the transfer market.
Mancini said of the talented youngster: "He scored a great goal and moved very well and I must say I liked him."
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