"We're attacking very well, but we're allowing too many goals," Ancelotti said. "It's an important game for Juventus but for us it's an opportunity to qualify for the next stage. The sooner we do that, better for us."
Goalkeeper Diego Lopez should give way to Iker Casillas despite an extraordinary performance at Rayo, while Raphael Varane returns to the center of defense to replace either Pepe or Sergio Ramos. Midfielder Xabi Alonso is also expected to play in the Champions League for the first time this season.
Juventus is counting on its local support and impressive home record against Madrid.
The new Juventus Stadium has proved somewhat of a fortress in the Champions League with Bayern Munich the only team to emerge victorious in Turin. In its old stadium, Juventus had lost only twice in the competition in 10 years.
"We need to make our home advantage count because, apart from determination and the right tactics, the atmosphere will be important," Conte said. "I'm expecting our fans to provide a red-hot atmosphere, not only when the game is going our way but also when the game isn't going our way. They need to push the players to overcome a hurdle, a very high one at that."
Madrid hasn't won at Juventus since 1961-62. Since then, Juventus has racked up five straight wins over its Spanish rival.
The last time either team won away was 1986 when the Italians won at the Bernabeu.
Galatasaray can take a big step toward reaching the knockout stage, but it will have to do it without two key players.
Goalkeeper Fernando Muslera is likely to sit out the trip to Copenhagen with a broken toe, leaving backup Eray Iscan to make his first appearance since undergoing knee surgery in September.
Wesley Sneijder's nagging right thigh could also keep the Netherlands midfielder from taking part.
The Turkish club can take a big step toward advancement with a victory, but Copenhagen is unbeaten at home in the group stage over the past eight seasons, including a 1-1 draw against Juventus this season.
Associated Press writer Daniella Matar in Milan contributed to this report.
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