His 57th-minutae strike, which completed the scoring on Wednesday night, saw the Portuguese superstar equal Alfredo Di Stefano's club record of 49 goals in the European Cup for Los Blancos.
The Ballon d'Or winner's 14th goal of this season's competition also saw him equal Lionel Messi's record, set in 2011/12, for the most goals scored in a single Champions League campaign
But it was not all good news as a knee injury saw Ronaldo substituted with 10 minutes remaining.
Any time the 29-year-old gets hurt it is the subject of much consternation in the Spanish capital but Real manager Ancelotti has played down the problem.
Speaking at his post-match press conference at the Bernabeu, the Italian said: ``Ronaldo had a knee problem but I took him off to avoid any risks. He is not injured, just a minor annoyance.
``This is not something to be worried about right now. We are not worrying about it. We will let him rest but right now we're nothing thinking about it because the player is relaxed.
``I took him out for 10 minutes. I believe we will wait until we are worried.``
It was reported in the build up to the Borussia Dortmund tie that Ronaldo's knee had been bothering him so it remains to be seen whether he will be involved when Madrid resume their La Liga title challenge at Real Sociedad on Saturday.
Ideally, perhaps, Ancelotti would like to rest his star man but with Real third in the table, two points behind Barcelona and three adrift of city rivals Atletico who lead the standings, Los Blancos can ill afford any mistakes as the title run-in hots up.