Twice European Champions Benfica fought back to secure a 2-1 win at Juventus with goals from Joao Mario and David Neres on Wednesday, maintaining their perfect start in Champions League Group H.

It was a miserable night for Juventus, who have lost their opening two games of the Champions League group stage for the first time and lost three games in a row in Europe's elite club competition for the first time in 50 years.

"I already told the team these moments happen in football, we need to emerge from them as a team, with a sense of responsibility," Juventus coach Massimiliano Allegri told Sky Sport Italia.

"We have an important game coming up against Monza and after that we can think about Europe. It will certainly be difficult, but not all is lost." Juventus took a fourth-minute lead when Arkadiusz Milik climbed highest inside the box to head the ball into the bottom-left corner from a Leandro Paredes set piece.

The early goal seemed to take Benfica by surprise, as the first 25 minutes of the game was dominated by Juventus, who pushed the Portuguese team onto the defensive. Benfica had their first real chance after 27 minutes when Neres crossed for Goncalo Ramos, who managed to head the ball right at Juventus keeper Mattia Perin.

As half-time approached, Benfica began to gain more control and possession as the pressure from Juventus eased. The visitors were awarded a penalty in the 43rd minute following a VAR check after Juventus midfielder Fabio Miretti fouled Ramos inside the box and Mario equalised from the spot.

Benfica maintained their momentum in the second half, with Neres putting them ahead in the 55th minute, firing home on the volley after Rafa Silva's shot had been parried into his path by Perin.