Higuain scored early on and then set up Federico Bernardeschi's goal after the break before Ronaldo added the third in the 89th. Higuain was loaned away to AC Milan and Chelsea last season but is back with Juventus under new coach Maurizio Sarri, who also coached "Pipita" at Napoli.
"I came here with great determination," Higuain said. "I wanted to prove I could stay here." With Atletico beating Lokomotiv Moscow 2-0 in the other Group D game, Atletico and Juventus moved atop the standings with four points each. Lokomotiv is next with three and Leverkusen has zero.
"It was an important game after our draw in Madrid," Higuain said, "so we knew we needed the victory to get closer to qualification." When Jonathan Tah failed to clear a long ball from Juan Cuadrado, Higuain was waiting and used two touches to find the target with an angled shot from the edge of the area 17 minutes in.
Ronaldo was off target for much of the night and failed to take advantage of an enticing setup from Cuadrado near the hour mark as goalkeeper Lukas Hradecky stopped his low shot. Minutes later, however, Ronaldo started the action that led to Juve's second goal with a through ball for Higuain, who pulled it back from the endline toward the Portugal star. Ronaldo couldn't connect and Higuain's ball reached Bernardeschi, who fired in from the center of the area.
Miralem Pjanic nearly made it 3-0 with a corner that hit the post before Higuain set up Ronaldo for another excellent chance wasted by the five-time Ballon d'Or winner. Higuain had already exited to a standing ovation when Ronaldo finally found the target after taking a through ball from substitute Paulo Dybala and scoring with a precise, angled drive.
It was Ronaldo's 127th goal in 164 Champions League matches. Eight-time defending Serie A champion Juventus visits Italian league leader Inter Milan and former coach Antonio Conte on Sunday.
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