Cristiano Ronaldo to miss Juventus clash against Atalanta in Serie A

Maurizio Sarri aims to have star striker back for next week's Champions League match at home to Atletico Madrid

Juventus forward Cristiano Ronaldo was substituted by manager manager Maurizio Sarri in their last two matches. AFP

Cristiano Ronaldo is set to miss Juventus' Serie A clash with Atalanta, despite being in fine goalscoring form for Portugal this week.

Juve are looking to extend their unbeaten run this season to stay top of Serie A, before hosting Atletico Madrid in the Champions League next week.

Maurizio Sarri's side are just one point ahead of Antonio Conte's Inter Milan after 12 matches, with Lazio and Cagliari eight points adrift of the leaders in joint third.

Ronaldo admitted that he has been playing "at a slightly reduced capacity" of late, with Sarri saying the Portuguese star has a "little knee problem".

The 34-year-old also admitted that he was frustrated at being substituted early on in the second half of Juve's win over AC Milan in their last Serie A match, four days after being withdrawn against Lokomotiv Moscow in the Champions League. "I don't like to be replaced, no one does. I tried to help Juve even when injured," he said.

Sarri, though, insisted he has no problem with Ronaldo, who scored a hat-trick for Portugal in their 6-0 thrashing of Lithuania last week before netting his 99th international goal in Sunday's 2-0 win against Luxembourg.

"There is no need to explain his reaction to being substituted," Sarri said on Friday. "Even among amateurs the reaction to being substituted is the same.

"If anything, the problem is that on Tuesday he told us he had the same issue and we have prepared a programme that will allow him to overcome the problem.

"There is a 99 per cent chance he will not be available for tomorrow's game. The goal is to be ready for the Champions League match with Atletico Madrid."

Juventus will be without full-back Alex Sandro, who picked up a thigh problem playing for Brazil, but French midfielder Blaise Matuidi should be available despite a rib injury sustained against Milan two weeks ago.

Atalanta have gone three league games without a win and will be eager to get back into the Champions League berths, as they sit two points off fourth place, before next week's trip to Shakhtar Donetsk.

Atalanta's fortunes have slipped following the thigh injury suffered to Colombian star Duvan Zapata, who scored six goals in six Serie A matches before being sidelined for their last five league games.

Juve full-back Danilo, who scored his first goal for Brazil during the international break, warned his teammates that Atalanta should not be taken lightly.

"The games after the international break are never easy, let alone against Atalanta, a team who are doing well," he said. "We can't make mistakes or underestimate them."

It was a sentiment echoed by Sarri. "They have a way of playing with great intensity. To call it annoying is an understatement," he said. "They are a strong and dangerous team, one that is difficult to face.

"Pep Guardiola explained playing against Atalanta the best way; facing them is like going to the dentist. They are technically good as well as aggressive. It won't be easy, especially away from home'

"But changing mentality for a single opponent is impossible. It takes months to build a mentality – we have to go our own way."

Inter will be looking to make it a perfect seven league games on the road this season as they travel to Torino, before their European trip to Slavia Prague.

Conte's side face a tough task against the Andrea Belotti-powered Torino, who ended their six-match winless run against Brescia last time out, and are in 11th position.

Serie A runners-up Napoli are in crisis, having slipped to seventh, and desperately need a result at 14th-placed AC Milan, who are themselves floundering.

Carlo Ancelotti's Serie A runners-up last season head to Milan amid reports he has two games left to save his job. Napoli have gone four games without a win in Serie A and sit seventh.

After being held 1-1 by Salzburg in the Champions League, they travel to Liverpool next week in a key game for the former Chelsea, AC Milan and Real Madrid manager.

Cagliari and Lazio will look to continue their strong form at lowly Lecce and Sassuolo, respectively.

Roma have a chance to move into the Champions League places as the look to bounce back from last week's defeat to Parma at home against tailenders Brescia.