Serie A returns after a two-week international break with former Real Madrid player Ronaldo, who skipped Portugal's duty to focus on his new club, as did his teammate, Croatian runner-up Mario Mandzukic. .
During the break, the 33-year-old man was photographed resting on board his yacht in front of Saint Tropez in the French Riveria.
"Vitamin D," wrote the five-time Golden Ball winner under a picture of him resting on the deck of his yacht.
"As my teammates say, back to reality, work done," he later published. "You feel good! Let's go."
Coach Massimiliano Allegri says he is not worried that Ronaldo could not find the net despite 23 shots on target in three games.
"It takes time, we will all be fresher after the break and that's when the real season starts," said Allegri.
Ronaldo had to wait until his fourth game with Real Madrid last season to get his first goal in the league.
German midfielder Sami Khedira said in an interview after his contract at Juventus extended this week that the Portuguese star was brought not to accumulate goals, but to make a difference in the Champions League and turn "dreams into reality" .
Juventus beat Sassuolo 7-0 in their last game last season, but the Modena club had a good start in this campaign and are behind the champions in the table after two wins and one draw.
Allegri will be eager to rotate his team with a tight schedule of seven games in 21 days, and defender Andrea Barzagli stopped playing due to a calf problem.
Argentina's Paolo Dybala, Juventus' top scorer in Serie A last season, and Brazil's Douglas Costa seem ready to start on the bench.
Despite being overshadowed by the arrival of Ronaldo, Dybala insists that he feels lucky to play on the same team as the five-time Golden Ball winner.
"I told myself that after having had the good fortune to play with Lionel Messi on the national team, I have now had the opportunity to play alongside Ronaldo," said Dybala.
Napoli, Roma and Inter Milan also have Champions League games in their minds.
Rome hosts Chievo on Sunday after his defeat to AC Milan before the break, and before a trip to Spain to face reigning champions Real Madrid.
Inter Milan play at home against Parma on Saturday before playing at Tottenham Hotspur at San Siro in their first European game since the 2011-2012 season.
Luciano Spalletti's Inter, with star forward last year Mauro Icardi struggling to get rid of a muscle injury, comes from a 3-0 victory over Bologna after only one point in his first two games.
Carlo Ancelotti will look to put his first Napoli coach loss behind him when runner-up Fiorentina last season before playing against Red Star in Belgrade on Tuesday.
Fiorentina has won two games with his first match against Sampdoria postponed due to the Genoa bridge disaster.
AC Milan heads to Cagliari in Sardinia with former Juventus striker Gonzalo Higuain also hoping to score his first goal for his new club.
Inter Milan v Parma, Napoli v Fiorentina, Frosione v Sampdoria
Roma v Chievo, Genoa v Bologna, Juventus v Sassuolo, Udinese v Torino, Empoliv Lazio, Cagliari v AC Milan
SPAL v Atalanta