The Pole now has scored four goals in three games.
"Sure, Polish football is not as difficult as Serie A, but Genoa is the same league as Milan. I scored goals all the time there, so I just have to keep my focus and mentality," he told Sky Sport Italia after the 3-0 win.
“I feel very good here, I want to score in every match, so we'll see."
Milan coach Gennaro Gattuso said Piatek was like Robocop.
“I prefer Pistolero!" he replied, referencing his trademark 'guns' celebration.