A win seemed be out of the Rossoneri’s reach after Mark Van Bommel was sent off in his Serie A debut in the 54th minute but goals from the Brazilian and Zlatan Ibrahimovic gave the visitors three vital points.
Robinho hailed his side's performance and believes the Diavoli showed their championship mettle after leaving the Angelo Massimino cauldron with all three points in tow.
"I'm very happy with the win tonight," he told Sky Sport Italia after the final whistle. "It's a difficult place to play especially against a team that defends well. We are first in the standings with 15 to 20 games left and we must continue to play well.
"It's difficult to play with ten men and in my opinion Van Bommel did not deserve his second yellow card," Robinho concluded.
Milan have a seven-point cushion at the top of the table ahead of Sunday's matches in Serie A.