Real Madrid took a giant step towards the La Liga title with a hard-fought 3-2 win over Sporting on Saturday.
Madrid are also still in the Champions League, and are favourites to reach the semi-finals after a 2-1 win over Bayern Munich in midweek.
Zidane is desperate for more success and is aiming to make history by becoming the first manager to defend Europe’s top club competition in the modern format.
Cristiano Ronaldo thinks Toni Kroos is so important for Real Madrid Real Madrid wages revealed: Which stars earn most? Fri, March 24, 2017
Click to reveal every Real Madrid player's weekly wages, according to Totalsportek.com
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Click to reveal every Real Madrid player's weekly wages
And Spanish outlet Don Balon claim Ronaldo thinks Kroos is essential in their pursuit of glory.
The Germany international has been in fine form in recent weeks, helping Real maintain their bid for success on all fronts.
Ronaldo is said to believe Luka Modric is past his best and feels Kroos is now even more significant than before.
Toni Kroos has emerged as a key player for Real Madrid
The former Manchester United star also thinks Isco, who has been linked with Barcelona, deserves more game time.
Ronaldo was rested for the win over Sporting but is expected to start when Real face Bayern on Tuesday.
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