After dropping points to Valencia and Las Palmas, Zinedine Zidane took a risk in heavily rotating against Eibar, and it seems to have paid off as Los Blancos captured all three points and left plenty of starters rested for the key midweek clash.
Dani Carvajal, Marcelo, Toni Kroos, Cristiano Ronaldo and Gareth Bale all took the weekend off, and all five are expected to feature against the Italian side.
Furthermore, Casemiro, Luka Modric, Pepe, and Karim Benzema all rested against Las Palmas, so they too will be particularly fresh.
Only Sergio Ramos and Keylor Navas of the expected starters played in both of those matches, meaning Los Blancos will have plenty left in the tank against Napoli.
In Italy, there will be no room for rotation, and no margin for error, but Zidane can take comfort in the fact that his XI will be amongst the fittest he has played all season.