Stefano Pioli is looking forward to Zlatan Ibrahimovic's return, but the Milan coach was pleased with Rafael Leao's performance against Sassuolo.

Leao scored the fastest goal in Serie A history – after just six seconds – as Milan recorded a 2-1 win over Sassuolo on Sunday.

Milan returned to winning ways after back-to-back draws, and they are a point clear of rivals Inter atop the table.

Pioli's men have managed to stay unbeaten in Serie A through 13 games despite being without Ibrahimovic since the end of November, the striker – who has scored 11 goals this season – set to miss another month after suffering a calf injury in training.

Despite his side's form without the 39-year-old star, Pioli is keen to welcome Ibrahimovic back.

"First of all, with Ibra we are a stronger team. He is a champion and with him the team improved under many aspects," he told a news conference.

"Thanks to his work many players have improved their performances. I hope he can come back as soon as possible because we need him and with him we are a better team."

Leao, 21, is the youngest player with three-plus goals in the top five European leagues in each of the past three seasons.

Alexis Saelemaekers doubled Milan's lead after the early opener and they saw out a win despite Domenico Berardi's late strike.

"I'm very happy for Leao because sometimes I ask him more in terms of determination and consistency during the game," Pioli said.

"I never judge a performance by the goal but today despite scoring he had a good approach to the game and he worked a lot also when we were defending and was able to help the team a lot.

"He did all these things and with his individual qualities if he shows this mentality he can become a very important player if he plays like he did [against Sassuolo]."