The Montenegrin scored both goals, including a deft curler for his second, though they came towards the end of another inconsistent display in which he missed an open goal and decided to shoot from a tight angle when team-mate Emanuele Giaccherini was in a better position.
Vucinic, who now has nine league goals this season, at least managed to draw a smile from his manager, Antonio Conte.
Conte, usually taciturn, joked that Vucinic's performance was so baffling he might have to drop him for Wednesday's game, when Juventus hope to overturn a 2-0 deficit in their quarter-final, second leg at home to Bayern.
"I said to him afterwards that he had a strange match. He scored two goals - imagine what he could have done if he'd played well," Conte told reporters.
"The important thing is that he scored two goals, and I hope that's a good sign for the match with Bayern, because I'm thinking about putting him on the bench for it after that performance."
Conte is aware of the size of the task against Bayern, who clinched the Bundesliga title on Saturday by beating Eintracht Frankfurt 1-0.
"If we want to impose our rhythm on the game we have to go after them," Conte said. "Obviously then you risk what happened in the first game, where (Arjen) Robben and (Franck) Ribery find themselves one-on-one with our central defenders.
"They're a brilliant side. They're 20 points ahead of Dortmund, and that's a statistic that speaks for itself."