Cristiano Ronaldo will miss his reunion with Lionel Messi after another positive Covid-19 test ruled him out of Juventus' Champions League match against Barcelona.
Ronaldo has been self-isolating since he tested positive while on international duty with Portugal on October 13.
He returned another positive result last week, but underwent further testing in a bid to prove his fitness ahead of Juventus' blockbuster tie against Barcelona on Wednesday.
But Sky Italy confirmed Ronaldo failed to test negative 24 hours ahead of kick-off, as required by UEFA in order to play.
The 35-year-old's potential reunion with rival Messi was the standout fixture when the Champions League groups were drawn.
The pair, who have 11 Ballon d'or titles between them (Ronaldo, 5, Messi, 6), have not faced each other in the Champions League since the semi-final between Real Madrid and Barcelona in the 2011/12 season.
Ronaldo has missed three matches for Juventus since he tested positive, a victory over Dynamo Kiev in their Champions League Group G opener last week and two draws in Serie A.
He has been asymptomatic and posted regular updates on social media showing his home workouts and boasting a new buzzcut.
Barcelona head into Wednesday's tie against Juventus in crisis, with president Josep Bartomeu and the club's entire board having resigned from their positions on Tuesday night.
The 3-1 El Clasico defeat to Real Madrid last weekend appeared to be the final straw after a summer which saw Messi threaten to leave and accuse Bartomeu of lying to him.
As well as Ronaldo, Juventus will definitely be without Giorgio Chiellini and Matthijs de Ligt, with Weston McKennie also likely to miss out.
Pirlo is also sweating on the fitness of fellow defender Leonardo Bonucci with Paolo Dybala expected to feature after starting his first game of the season against Hellas Verona at the weekend.
Barcelona will be without the suspended Gerard Pique, who was sent off against Ferencvaros, while Marc-Andre ter Stegen, Samuel Umtiti and Philippe Coutinho are also sidelined through injury. Neto is expected to continue in goal.
There will be familiar faces on both sides too. Miralem Pjanic - now at Barcelona - and Juventus midfielder Arthur having switched between the two clubs in the summer, with goalkeeper Neto having also played for the Italian side previously.