Massimiliano Allegri said Cristiano Ronaldo is mentally stronger than others as the Juventus head coach praised the superstar following his goalscoring display against Frosinone.

Ronaldo put Champions League heartache aside to lead Serie A holders Juve to a hard-fought 2-0 win at Frosinone on Sunday.

Five-time Ballon d'Or winner Ronaldo was reduced to tears after being sent off against Valencia in the Champions League but the former Real Madrid forward redeemed himself with Juve's 81st-minute opener.

Chances did go begging for Ronaldo but the 33-year-old remained composed to deliver, much to the delight of Allegri.

"Cristiano Ronaldo had many chances and that happens because good balls always end to players that are able to score goals in the box," Allegri said.

"He missed some of these chances, in a few occasions he has been unlucky with the rebounds, but his strength is the fact that he is always into the match, even if he doesn't score straight away.

"And that's what happened because to score a goal like that towards the end means that he has a mentality stronger than the others."

Ronaldo has now scored three goals in his past two Serie A matches as Juve top the league standings by three points after five games.