The Serie A side went into the tie as hot favourites, but after a 1-0 loss at Parc OL it remains in the balance.
Juve turned in a desperately poor first-half display, during which they conceded to Lucas Tousart, and Ronaldo and Dybala have pointed the finger of blame towards the team’s midfielders.
While waiting in the tunnel for the second half of the fixture to begin, the pair were having a chat, apparently unaware that there was a television camera behind them picking up the nature of their conversation, which took place in Spanish.
“We are left alone out there, the midfielders are giving us no support,” the five-time Ballon d’Or winner grumbled to his colleague.
“Nobody is getting the ball,” Dybala replied.
“I know, not even the second balls, nothing,” Ronaldo said.
While Juventus did improve in the second period of the fixture, they were unable to hit back and indeed failed to muster a single shot on the French side’s goal over the course of the 90 minutes.
It was a result – and performance – that served only to increase the pressure on head coach Maurizio Sarri, whose side have slipped to second in the Serie A standings behind Lazio, albeit having played one game fewer.
Juve, so used to being the dominant force in Italy, have won only three of their last seven games in all competitions.
Meanwhile, they will not have the opportunity to absolve themselves on Sunday, with their encounter against Inter called off because of coronavirus fears.
It is one of five encounters to have been postponed in Italy this week due to concerns that large crowds could increase the spread of the illness.
The fixture has instead been schedule for Wednesday, May 13.
There has been no suggestion that the second leg of the Champions League last-16 match against Lyon could be thrown into doubt, however, with that encounter still pencilled in for March 17 at the Allianz Stadium.