The 33-year-old has denied rape allegations levelled against him by a woman who sued him in court in the United States.
"Cristiano Ronaldo is fine," Allegri said.
Regarding the tribulations, he’s a lad I’ve known for three months. What I can say about him is that in his 15-year career, he’s always shown great professionalism both on and off the field. Calmness on and off the field.
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"As far as on the field matters - he is ready to play."
Ronaldo was not included in the Portugal national team squad announced on Thursday for their upcoming games, but Allegri said that was a decision he was already aware of.
“I knew he wouldn’t be called up by Portugal, he reached an agreement with the national team coach and president of his federation not to go.
"It is better for us because he will spend more time working with us. He is in a delicate moment but he has broad shoulders, he’s focused on taking to the field and doing well.”

Cristiano Ronaldo (Juventus)

Image credit: Getty Images

Sportswear maker Nike Inc and video game maker Electronic Arts Inc said on Thursday they were concerned about the allegations against Ronaldo.
Shares in Juventus fell sharply on Friday, with a trader attributing the move to the allegations.
"We are deeply concerned by the disturbing allegations and will continue to closely monitor the situation," Nike said in a statement to Reuters on Thursday.
Nike has worked with Ronaldo since 2003 and in 2016 announced a lifetime deal with him which could be worth as much as $1 billion, according to Forbes magazine.
Electronic Arts has featured Ronaldo on the cover of its EA Sports' FIFA series for two years. An EA spokesperson said on Thursday it was also closely monitoring the situation.
“We expect cover athletes and ambassadors to conduct themselves in a manner that is consistent with the EA's values," the company said.

Cristiano Ronaldo

Image credit: Getty Images

Kathryn Mayorga sued Ronaldo in a district court in Clark County, Nevada, alleging he raped her in 2009 in a Las Vegas hotel penthouse suite.
Ronaldo has said his conscience was clear and that he would await the results of any investigation.
"I firmly deny the accusations being issued against me. Rape is an abominable crime that goes against everything that I am and believe in," Ronaldo wrote in a tweet to his 75 million followers.
Ronaldo moved from Real Madrid to Italian champions Juventus this summer for 100 million euros.
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