Nine months on from winning the 1998 FIFA World Cup, Zidane, a Ballon d'Or recipient, had an uncertain future under Ancelotti, from Corriere dello Sport via Jon Brodkin and Michael Walker at The Guardian:
The Italian sports daily Corriere dello Sport yesterday cited club sources in a story that the 26-year-old will leave Juventus for Old Trafford or a Spanish club at the end of the season.
Zidane, it said, is not considered essential to the tactics of Carlo Ancelotti, who replaced Marcello Lippi as coach earlier this year.
The 1999 version of Ancelotti was stubborn to a fault, dogged in defence and had a philosophy that leaned more towards catenaccio than total football.
During Ancelotti's time at Parma, he was notorious for his refusal to adjust his tactics according to the creative flair of the players he had at his disposal.
Forget about Adaílton, Jesper Blomqvist and Tomas Brolin; Gianfranco Zola was the biggest casualty.
"I made a mistake with Zola because I wanted to play 4-4-2 but he wanted to stay in the centre like a striker," reflected Ancelotti via The Guardian. "He would probably not have gone to Chelsea if I had changed the system."
When Roberto Baggio, then with AC Milan, approached Parma regarding a potential move, Ancelotti sunk the deal because he didn't want to build the team around il Divin Codino.
Baggio would have been divine for Parma, but he signed with Bologna and scored 22 times in 30 Serie A games, six more goals that season than Enrico Chiesa and Hernán Crespo combined.
"I played with a 4-4-2 formation and I didn't want to change, so I didn't take Baggio," Ancelotti said to BeIN Sport via Ian Holyman at ESPN FC. "If I could do it over, I would sign Baggio and only then talk about where he would play on the pitch.
With Fabio Cannavaro, Gianluigi Buffon, Lilian Thuram, Néstor Sensini and Roberto Mussi, Ancelotti had no intentions of Parma emulating Zdeněk Zeman's Foggia side of the early '90s, a team that played football with bravado and no fear.
Parma finished two points behind Juve for the 1996-97 Scudetto, however 13 teams scored more goals than Ancelotti's side.
When he replaced Marcello Lippi at the Bianconeri, an already disgruntled Thierry Henry, wasted in Lippi's 3-5-2, was Ancelotti's next high-profile victim.
"I didn't think I could play Henry in the middle and he never told me he could," Ancelotti told Philippe Auclair via Thierry Henry Lonely at the Top: A Biography. "Henry didn't leave because he had a problem with me, or me with him, his problem was with the club."
Arsenal manager Arsène Wenger, who worked with Henry at Monaco, bought the Frenchman and changed him into a centre-forward—Henry went on to score 228 times for the Gunners.
The key difference between the situations of Henry and Zola compared to Zidane was that Ancelotti didn't want Zizou to leave.
"When I arrived at Juventus I changed my view and that was because of Zidane," Ancelotti said via Rob Shepherd at The National. "How could I play such a great talent wide on the left or the right in a 4-4-2?"
Instead of being known as the manager who was too headstrong to experiment with Baggio, Henry and Zola, Ancelotti was now more open to change because he was forced to abandon his inflexible, rigid and limited formation for Zidane.
At AC Milan, Andrea Pirlo, then a No. 10, was the first to profit from Ancelotti's new-found tactical adaptability, from Preferisco La Coppa via The Daily Mail:
Pirlo approached me one day and suggested that he could play in a deep-position, just in front of the back four. I was extremely skeptical. He was an attacking midfielder, his tendency was to run with the ball. And yet, it worked. He became one of the best in the world in that role.
Kaká, an €8.5 million signing from São Paulo, wasn't going to become Henry 2.0 for Ancelotti.
Early on in Kaká's career, Ancelotti surrounded the Brazilian with three playmakers in Pirlo, Clarence Seedorf and Rui Costa, coupled with a world-class No. 9 in Andriy Shevchenko.
There was no way a player of Kaká's talent was going to fail with that much assistance.
During Kaká's pomp, he was often a deep-lying forward playing off Filippo Inzaghi, and the freedom to roam enabled the Brazilian to win the 2007 FIFA World Player of the Year.
He became Ancelotti's penance for not projecting Henry's upside.
Having won two Champions League titles for AC Milan, Chelsea owner Roman Abramovich arranged a secret meeting with Ancelotti.
"My Chelsea team don't have a personality," Abramovich told Ancelotti from Preferisco La Coppa via The Independent. "My ambition is to win every competition but at the moment I don't even recognise my team."
Under Ancelotti, the Blues became the first Premier League team to score 100 goals or more in a season.
His inability to win the Champions League led to him saying arrivederci to Stamford Bridge and bonjour to Paris Saint-Germain.
Whether it was a 4-1-2-1-2, 4-3-3, a 4-2-3-1 or a 4-2-2-2, Ancelotti's propensity to experiment is linked back to him having to adapt to Zidane at Juventus.
Ancelotti had to figure out a way to include Ezequiel Lavezzi, Javier Pastore, Jérémy Menez, Lucas Moura and Zlatan Ibrahimović in the PSG starting XI.
Ancelotti is coming to Real Madrid with league titles in Italy, England and France.
Carlo Ancelotti/Zinedine Zidane Real Madrid Partnership
Do you know who the perfect manager is to deal with Cristiano Ronaldo's discontent? Ancelotti.
In 1999, the Italian had a more sizable task because Zidane had already announced his decision to leave Juventus, via The Independent:
I want to play in Spain. I don't know when but one day I will. My wife is Spanish, we have Spanish friends and I want to move there. I have never hidden my problems about the life here in Turin.
Juventus have shown that they can win the big matches but my wife, my family and my lifestyle count more than my job.
Ancelotti was in a lose-lose situation but went outside his comfort zone and tinkered the formation to bring the best out of Zidane, who claimed he would have won another Ballon d'Or if it wasn't for his on-field indiscretions.
This prevented Zidane's market value from plummeting, and Juventus received a then-world record transfer fee of €75 million from Real Madrid.
What Florentino Pérez doesn't want is Ronaldo to fall out with management as he did last season.
"I had only one problem with him," Ancelotti's predecessor José Mourinho said via The Guardian. "Ronaldo thinks he knows everything and the coach cannot help him to develop more."
Pérez knows Ancelotti's easy-going personality combined with the presence of Zidane will provide the foundations for Ronaldo to keep his transfer stock from falling.
When Ancelotti said, "We scored a lot of goals with Milan as well as Juventus, PSG and Chelsea," via RealMadrid.com, he conveniently left out Parma.
"My idea is to play attacking and spectacular football," he said. "Real Madrid’s history and tradition are to play offensively."
It was his assistant manager, Zidane, who prompted Ancelotti to overhaul his footballing mentality 14 years ago.
Without Zizou, Ancelotti would have become a Fabio Capello clone.