A left post from Alex Sandro cut through the entire penalty area, away to the Swede who with his left foot placed 1-0 for Juventus against his ex-club in the 23rd minute.
It was Kulusevski's third goal in Serie A this season and he celebrated restrainedly.
Just three minutes later, Cristiano Ronaldo increased the lead when he nodded in 2-0 for "Juve".
42-year-old Giangluigi Buffon is in goal for Juventus against the club he made his debut for in 1995. Just before Kulusevski's management goal, he saved Juventus from an early setback.
The match is in progress and is 2-0 to Juventus.