The Italian boss was impressed by Rooney’s demolition of AC Milan in the Champions League on Wednesday.
Mancini told Gazzetta dello Sport: “He is the best in the world with Messi.
“He scores loads, works for the team and is intelligent all over the pitch. Rooney is their most important player.
“He is very valuable to the team but it is not only him. The rest of the Manchester United team are also good. Did you see Park? He was always on Andrea Pirlo and did not let him play and then even scored.”