The Portuguese sensation recorded the quickest top-flight century in the club's history as they avoided dropping points for the third Primera Division game in a row
The Portuguese's first arrived just after half an hour and it gave him a century of goals in the Spanish top flight after only 92 games, making him the fastest player to reach that milestone in the capital outfit's history.
Gonzalo Higuain's early opener and a double from Karim Benzema completed the rout for the home side, who, after drawing their last two league games, picked up a crucial three points to maintain a six-point gap over Barcelona. Xabi Prieto's strike minutes before half-time was nothing more than consolation for the visitors.
The absence of Jose Mourinho, suspended after being sent to the stands against Villarreal in midweek, did not faze Madrid as they broke the deadlock after only six minutes. Benzema strode in down the right flank and teed up Higuain for a sweeping finish from the top of the box to beat Claudio Bravo in the visitors’ goal.
The hosts, buoyed by the opener, began to push forward more in the Sociedad half in their quest for a second, with Ronaldo at the end of a pair of great chances. The Portuguese first saw a stinging effort blocked by Bravo before sending a header wide from a position where he really should have hit the target.
However, Ronaldo was not to be denied and with 33 minutes gone, he came up with the goods at the third time of asking, running on to Kaka’s through ball and placing his finish into the far corner.
The goal, his 100th in the league in 92 appearances, comfortably surpassed the long-standing club record of Hungarian Ferenc Puskas, who reached the landmark tally in 105 games.
It was one way traffic thereafter, and Benzema struck five minutes before the break to make it 3-0, latching on to a superb long ball from Xabi Alonso and cushioning it down with his chest before lobbing the on-rushing Bravo.
However, Sociedad pulled a goal back almost immediately with a long-range strike from the left by Xabi Prieto that nicked off the head of Sergio Ramos en route to the far corner.
It proved to be nothing more than a consolation, however, as within four minutes of the restart, Benzema took Sami Khedira’s pass into his stride before slotting into the corner to restore the hosts’ three-goal advantage.
In the 56th minute, Madrid made it 5-1. Higuain did the hard work, sprinting in from out wide and squaring to Ronaldo at the far post, who made no mistake to score his 35th league goal of the season, bringing him level with Lionel Messi in the race for the Pichichi trophy.
The visitors were floored at this point, and spent the rest of the match playing for the final whistle as Madrid continued to control the game. They went close again in the 78th minute, with Ronaldo picking out Fabio Coentrao in the area for a toe poke that flew inches wide.
With the game nearing its conclusion, Higuain let fly with a powerful drive that Bravo did well to tip over, before Raphael Varane’s header from the resulting corner was cleared off the line as Los Blancos ran out comfortable winners.
Madrid re-open their six-point lead over Barcelona at the summit of La Liga and in the process, avoided dropping points for the third league game in a row. Mourinho's men now travel to Cyprus to take on APOEL on Tuesday in the first leg of the Champions League quarter-finals.