Zinedine Zidane says Cristiano Ronaldo's hunger for success is crucial to Real Madrid as they prepare to take on Barcelona at Camp Nou on Saturday.
The 31-year-old has enjoyed a hugely successful 2016, winning the Champions League with Madrid as well as Euro 2016 with Portugal.
He continues to push for more, though, and Zidane is impressed with the prolific attacker's impeccable attitude.
"Ronaldo's energy and motivation is very important for the entire team," Zidane said at a news conference.
"He has won everything this year, but he is still hungry for success.
"He is a great professional and he knows how to prepare for a game like this. I do not have to say anything special to him, even if we speak regularly."
Ronaldo has netted eight times in Madrid's last four La Liga games, but Zidane was quick to stress there is more to Madrid than the former Manchester United star.
"I want to make all players feel important. All the players at Madrid are good players and important to the team," he added.
"Of course, I am not stupid and I realise that some players make the difference. But it is the team that is important."
Zidane welcomed Casemiro back to the fold this week, the Brazilian featuring for the full 90 minutes against Cultural Leonesa in midweek, but Toni Kroos remains unavailable for now, despite a return to training on Friday.
"I have already decided on my starting XI," Zidane continued.
"Casemiro is ready and we are happy to have him with us, he is very important to us.
"Kroos is not ready yet, he needs some more time."