Giorgio Chiellini led the way as Juventus players returned to individual training at the team's sports centre on Tuesday, while Cristiano Ronaldo began two weeks' coronavirus quarantine after returning to Italy.
Captain Chiellini, 35, arrived early with Italy defender Leonardo Bonucci, wearing a black face mask, just after midfielder Aaron Ramsey. Playmaker Miralem Pjanic showed up in the afternoon, along with Juan Cuadrado, Mattia De Sciglio, Federico Bernardeschi and Daniele Rugani.
Serie A champions Juve said the training sessions, which are allowed thanks to Sunday's green light from the Italian interior ministry, "will take place on an individual basis and with staggered arrivals to allow full compliance with the regulations in force".
"After a day of tests and exams carried out yesterday at J Medical, some of the Juventus players started training at the Continassa Training Centre, where they officially began their recovery to regain competitive form," Juve added.
Ronaldo's return is more uncertain after two months of confinement on his native island of Madeira, having played in Juventus' last match against Inter Milan on March 8 behind closed doors.
The five-time Ballon d'Or winner returned with his family to Turin by private jet late on Monday, and is in quarantine awaiting tests.
The interior ministry's go-ahead has allowed players to return to club training facilities two weeks ahead of schedule, offering a glimmer of hope that the 2019-20 season might yet be saved.
As well as Juventus, top-flight clubs Atalanta, Bologna and Udinese also got back to training on Tuesday, with Sassuolo and Lecce leading the way on Monday.
But sports minister Vincenzo Spadafora warned training in groups must wait until May 18, and it remains uncertain whether matches can restart as the country battles the Covid-19 pandemic which has killed more than 29,000 in Italy.
"A realistic prediction can be made in mid-May," Spadafora said in an interview with newspaper Corriere della Sera on Tuesday, denying he wanted to call a halt to the season.
"It would be surreal for a sports minister to demonise football," he said after a newspaper created a front-page photo of him with a dagger about to burst a ball, with the headline "Attack on Football".
"I hope to start again, but the government will decide ... There is no opposition from me, just the desire to evaluate a restart only if the health of the people within the team group will be safeguarded.
"If the government is forced, and I hope not, to admit that the conditions (needed to resume) are not there, my commitment will be twofold - limit the financial damage to clubs and support the whole world of sport.
"Between ordinary and extraordinary resources, we will invest about one billion euros ($1.08 billion) for the sector as a whole."
A meeting has been scheduled for Thursday between the Italian Football Federation (FIGC) and members of the government's Technical Scientific Committee to discuss the medical protocol for the resumption of group training.
European federations have a deadline of May 25 to inform Uefa if their league will resume, and if so on what date and with what format.