A goal just before the half was all the visiting side needed, despite a strong effort from the shorthanded home team.
Atletico Madrid made the most of Barcelona's El Clasico humbling by beating Getafe 1-0 to move within two points of the La Liga leader.
The reigning champion made the short trip across Madrid on Sunday and rarely looked troubled by its neighbor, claiming a victory to capitalize on Barca's 3-1 loss at Real Madrid 24 hours earlier.
Mario Mandzukic netted from close range five minutes before the break to send Atletico on its way, but things should have been far more comfortable as the team spurned numerous opportunities in the first half.
And after starting the second half encouragingly, Getafe handed Atletico a numerical advantage when captain Alexis earned a red card for striking Mandzukic in the face.
Despite finding themselves with an extra man, Diego Simeone's men seemed reluctant to throw players forward in search of a second goal that would have killed the game.
To its credit, Getafe attacked valiantly in search of an equalizer even though it was a man down, but Atletico's typically resilient defense held firm to seal all three points.
Atletico's dominance lasted through the first half and, after seeing efforts from Raul Garcia, Siqueira and Koke denied, it finally found the breakthrough after 40 minutes.
Vicente Guaita failed to hold on to Antoine Griezmann's half-volley, and Mandzukic stabbed home from close range after Arda Turan inadvertently knocked the initial rebound to the Croatian.
The hosts' hopes of drawing level suffered a significant blow in the 56th minute as their skipper Alexis received a straight red for striking Mandzukic on the side of his face, with tempers flaring on both teams.
Despite going down to 10 men, Getafe continued to press for an equalizer and substitute Baba Diawara went close just a few moments after coming on, sending a half-volley just wide from 25 yards.
But Atletico successfully repelled Getafe's spirited late efforts to find a leveler, meaning it could make the short journey home with a valuable victory.