The Serie A champions beat the Catalans at Camp Nou in the final group stage game to go top of Group G courtesy of the head-to-head rule.
Cristiano Ronaldo announced his return in Spain with a goal inside the opening 13 minutes from the penalty spot before Weston McKennie doubled Andrea Pirlo’s men’s advantage with an acrobatic finish.
Ronaldo got his second of the night from his second penalty seven minutes after the interval after VAR adjudged that Clement Lenglet had handled the ball inside his own box.
Barcelona had the lion’s of the ball and created a lot of chances but were kept at bay by Juventus.
“I think we lost the game in the first half-hour, as we got off to a bad start, didn’t play well defensively, were lacking aggression in midfield, and Juventus played well,” Koeman told Sky Sport Italia after the game.
“They were particularly strong in the first half-hour and deserved to win.”
The Dutch tactician was not convinced with some of the referee’s decisions, especially with Ronaldo’s first penalty and Juan Cuadrado’s tackle on Lionel Messi in the first half.
“You can also argue that the first penalty given wasn’t a spot-kick, while if they gave that one, then they ought to award one for the incident on Messi.”