Cristiano Ronaldo 'did well' in Juventus win at Chievo - Massimiliano Allegri

Ronaldo denied a scoring debut for Juventus (1:02)

The Cristiano Ronaldo era at Juventus begins with a dramatic last-gasp winner from Federico Bernardeschi. (1:02)

Cristiano Ronaldo missed several chances but was "was smiling because we won," Juventus manager Massimiliano Allegri said as he praised the Portuguese forward's Serie A debut in a 3-2 victory at Chievo.

Ronaldo, who signed for Juve from Real Madrid in July, took seven shots but was unable to open his account for the Italian champions as the league season got underway.

"I am sorry he didn't score," said Allegri after the game. "But we have been only working together seven days. He did well. [Paulo] Dybala and Ronaldo interchanged. You need to know the Portuguese well when you give him the ball. [Chievo goalkeeper Stefano] Sorrentino stopped [Ronaldo] a few times today. He made some good runs; at times they didn't pick him out."

Juventus were made to work hard for their victory: After taking a third-minute lead through Sami Khedira, they fell behind to goals from Mariusz Stepinski and Emanuele Giacherrini, a former Juve player whose penalty gave Chievo a 2-1 lead after 56 minutes.

But Mattia Bani's 75th-minute own goal drew the score level and, after substitute Mario Mandzukic had a goal disallowed following VAR consolation, fellow replacement Federico Bernardeschi tapped home the winner in the third minute of stoppage time.

"We knew it wasn't easy to play here, especially with this heat, but the important thing is to have heart," Bernardeschi said. "Champions are great, but football proved once again that nothing matters on paper, you have to prove it all on the pitch during the 90 minutes."

The game began with a minute's silence to remember this week's Genova bridge collapse tragedy.

"Unfortunately it was a national day of mourning so it was a strange day," Allegri said. "But we had to play. The lads played a good game. Chievo defended. They took the chances they had. Our concentration levels dropped. You let them cross, defend poorly in the penalty area and you concede. But we need wins like this. They immediately make you understand how hard it is to win again."

ESPN's James Horncastle contributed to this story.