Cristiano Ronaldo has failed to return a negative coronavirus test at least 24 hours before Juventus faces Barcelona in the group stage of the UEFA Champions League on Wednesday. This is Ronaldo's third positive test result since he was first diagnosed on October 13. He returned another positive test last Thursday, and another last night.

Ronaldo tested positive for the coronavirus two weeks ago, while on international duty with the Portuguese National Team. He missed their match against Sweden and flew a controversial return trip to Turin where he is spending his quarantine period.

Italian authorities are investigating his return, which may have violated the country's coronavirus safety protocols. The team announced that he flew back on a special private air ambulance, which the Italian authorities are calling "unauthorised."

Fans will have to wait until December to watch the highly anticipated reunion between Ronaldo and Lionel Messi. The two players had a heated rivalry in Spain, before Ronaldo transferred to Juventus from Real Madrid. It would have been a clash of the Titans this evening, but Juventus coach Andrea Pirlo will now have to make do without the Portuguese superstar.

Messi's fellow Argentine, Paulo Dybala, will likely start for Juventus to try to outplay his national team captain.

Sky Sports confirmed that despite having been allowed by UEFA to re-test just 24 hours before the game, Ronaldo was unable to produce a negative result. The player has remained asymptomatic ever since he picked up the infection following back-to-back Nations League games against Spain and France earlier this month.

Tonight's Champions League encounter will be the fourth match that Ronaldo has missed for the Italian club. He also skipped last week's opening victory against Dynamo Kiev along with two Serie A games. Juventus was held to two draws in both the Serie A matches.

In a press conference, Pirlo said, "We will count on the players we have available. Barcelona are strong and have great champions, we must play a great game. The players will certainly have to sacrifice themselves and play a great match. I'll go ahead with the back four because I only have four defenders. So, we'll go on like this."

Juventus vs Barcelona will be played at the Allianz Stadium at 8:45pm CET.

Cristiano Ronaldo
Cristiano Ronaldo AFP / Jonathan NACKSTRAND