Jose Mourinho's men registered their third win on a trot after their talismanic forward struck three goals to ensure his side maintained their momentum after an early-season blip
Los Blancos fell behind to a well-taken goal from Riki, but Ronaldo replied with a penalty, and then struck again before the break, after Angel Di Maria had edged the home side in front.
Pepe headed home a fourth midway through the second half before Ronaldo completed his hat-trick by converting his second spot-kick of the game six minutes from full-time.
With one eye on their Champions League clash with Ajax in midweek, Jose Mourinho made four changes to the side that claimed Los Blancos’ first away win of the season against Rayo Vallecano last week.
Sami Khedira returned to the midfield in place of Xabi Alonso and the German showed his early fervour at a recall by out-muscling his opponent in midfield to play in Cristiano Ronaldo for the first real chance of the game after 10 minutes, but the Portugal international struck his shot too close to Dani Aranzubia in the Depor goal.
Alvaro Arbeloa dropped to the bench as Sergio Ramos went to right-back to make way for Raphael Varane, and the young Frenchman will be disappointed with how easily he allowed Riki to skip away and poke past Iker Casillas to give Depor a shock lead after 15 minutes.
However, the hosts were level less than 10 minutes later when Di Maria beat Manuel Pablo on the right before the veteran brought him down right on the edge of the box. Referee Miguel Angel Ayza Gamez deemed the incident to have taken place inside the area, and Ronaldo stepped up to calmly stroke home the equaliser.
Jose Luis Oltra’s they had lost on their last six visits to the Santiago Bernabeu, their last victory coming way back in 2004, and never really looked like getting back into the game after an encouraging start.
The 36-year-old Pablo was made to endure a torrid time, with Di Maria and Ronaldo swapping flanks as Madrid repeatedly hit long diagonal passes in behind the former Spain international. And it was another ball inside the full-back that saw Di Maria put the home side ahead.
With Mesut Ozil returning to the side for the injured Michael Essien, Luka Modric took up a deeper role than he did last week and the two combined before the Croatian played a perfectly-weighted pass inside Pablo for Di Maria. The Argentine saw his initial effort come back off the post, but followed up to head home from close range.
Ronaldo grabbed his second goal of the evening five minutes later, heading into an empty net after Sergio Ramos saw his shot parried up into the air by Aranzubia.
Kaka also returned to the squad after netting a hat-trick in a midweek friendly against Millonarios on Wednesday, and he replaced Ozil to make his first appearance league of the season at half-time, with the German’s work rate was deemed unsatisfactory by Mourinho. It wasn’t a vintage performance from the Brazilian but the recall will no doubt be a confident boost for the 30-year-old - who looked to be on his way out of Madrid - especially when coupled with his return to the international fold this past week.
Xabi Alonso, who was the only outfield player at Madrid to have played every minute of the season so far prior to this game, replaced Modric on the hour mark, and less than 10 minutes later the Spain international’s in-swinging free kick found Pepe unmarked to make it four.
Ronaldo completed his hat-trick with eight minutes remaining, converting his second spot-kick of the night, after Kaka’s attempted cross had struck Evaldo’s hand inside the area.
Mourinho spoke of the importance of achieving three straight wins for the first time this season ahead of tonight’s game and despite still sitting eight points behind rivals Barcelona, Real Madrid’s return to form will provide them a well needed confidence boost ahead of next weekend’s Clasico.