Los Blancos and Kylian Mbappe may have struggled in Europe this season, but the Frenchman looked bright from the beginning and collected Brahim Díaz’s pass before firing into the bottom corner just 10 minutes into proceedings for his 50th Champions League goal.
Then he ran after seeing a poisonous strike that stopped through Marco Carnecchi.
Ademola Lookman asked questions at the other end, with a shot being blocked by Aurelien Tchouameni and a low cross for Charles De Ketelaere forcing a vital intervention from Antonio Rudiger.
Wderson has become the last player in having a shot blocked through Tchouameni and Lookman hit widely while the DEA intensified his search for a draw.
However, soon the sadness for Real Madrid, Mbappe, forced him to resume an injury in the 36th minute before Rudiger headed for a golden opportunity to double his team’s lead.
The centre-back’s frustrations were compounded when his partner Tchouameni tripped Sead Kolasinac to concede a penalty that De Ketelaere emphatically converted with the last kick of the half, especially as the German had previously exchanged heated words with the forward.
Supported at that point, Atalanta showed a target after restarting with Ketelaere emerging on Rudiger, but heading towards Fored Lookman courteous to a safeguard with their success in the strike.
However, they were in the 57th minute, as the ball bounced off Ederson and fortuitously fell to Vinicius Junior, who did his best with a clinical finish.
Three minutes later, Jude Bellingham cut off Marten de Roon and beat Carnesecchi to give his team a stamp.
Lookman swiftly offered a reminder that Atalanta weren’t out of the contest, smashing his shot through Lucas Vazquez’s legs and out of Courtois’ reach.
Diaz and Rodrygo wasted a chance apiece to regain some breathing space, but Courtois denied substitutes Lazar Samardzic and Mateo Retegui before the latter missed the target from a golden opportunity as Real Madrid saw out a vital win in response to their previous back-to-back Champions League defeats, going 18th in the standings for now.
They also inflicted Atalanta’s first European loss this term, although La Dea are still currently ninth.