Antonio Cassano has branded Cristiano Ronaldo "selfish" and believes the Juventus star is struggling to adapt to Andrea Pirlo's playing style.
Ronaldo has been the Turin giants' most productive player this season, scoring 23 times in 27 appearances so far.
But the 36-year-old had a quiet evening in midweek as his side were beaten 2-1 by Porto in the first leg of their Champions League last-16 tie.
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What was said?
While former Italy and Real Madrid forward Cassano admits Ronaldo is still at the top of the game, he believes he is going through a difficult spell this season.
"I have always said, even though he is a phenomenon and has scored a billion goals, that with Andrea Pirlo's idea of football he could run into difficulties," Cassano said to Christian Vieri on Twitch.
"He scores a goal per game, it's true, but he struggles with Andrea's idea. He's always been a bit selfish, he doesn't give a damn about others scoring goals.
"He's the kind of player that lives to score, not for the game, for the great match. He lives to score and in this moment the situation is getting worse. The years pass for everyone and he is having difficulties.
"The paradox is that Juventus have bought a player who has won five Champions Leagues but has so many difficulties in the Champions League.
"This is because, since [Maurizio] Sarri, Juventus are trying to show a style that is different to its history. It's clear that Pirlo must be judged in four or five years, but Juventus want everything immediately."
The current situation at Juventus
Not only are the Italian champions in danger of crashing out of the European competition, they have also fallen behind in Serie A.
Pirlo's team were beaten 1-0 by Napoli in their latest league match to end up eight points behind leaders Inter, though the Bianconeri still have a game in hand.
They are, however, through to the final of the Coppa Italia after beating Inter in the semi-finals.
Juve return to Serie A duty on Monday when they face Crotone. The second leg of their European clash against Porto will be played on March 9.