AC Milan coach Stefano Pioli was pleased after victory over Lecce.
Leao scored both goals for the 2-0 win.
Pioli said: "Rafa is an intelligent lad, we know that we're in the Champions League semi-final, but for the next few weeks we need to give our all in Serie A.
“I think Rafa ought to go more at the back post from open play as well as on corners. He is 1.90m tall, there are few full-backs who can deal with him physically in those situations. There are all these little areas he needs to improve on and we're working on them in training.
“We had patience, but not the same sharpness that we needed in the final third, where we made too many bad choices. We controlled the match as expected and ran hardly any risks."
On midfielder Rade Krunic, he added: “At the start he was more focused on breaking forward, but now he can build the moves too. He dictates the tempo in there, knows how to do everything. I also liked the way Ismael Bennacer came in today, the important thing is to take positions that cause problems for the opponents and give them doubts, as it opens up the spaces."