The Portuguese scored a wonderful long-range strike, picked up a booking for taking off his shirt in celebration and then received a controversial second booking for diving, before gently pushing the referee in protest.
Marco Asensio grabbed a third late on to all but settle the two-legged contest ahead of the return game at the Bernabeu on Wednesday.
Ronaldo could be in hot water though, with the Spanish Federation’s rules stating that a ban of 4-12 games can be handed out for physically confronting an official.
The La Liga opener against Deportivo comes this weekend, with their clasico rivals in a bad way after Neymar’s departure to Paris Saint-Germain.
After winning the double last season, Los Blancos look in fine form to repeat their success this season.