Radamel Falcao's poacher's goal 14 minutes from time gave Atletico Madrid a 1-0 away win over Sevilla that put them back within three points of city rivals Real in second place.
The Colombian poked home a shot from Raul Garcia to win a closely fought match that was high on intensity and tension but which produced little in the way of quality football.
Nine-man Getafe's hopes of qualifying for the Europa League suffered a blow as they lost 2-0 at home to Espanyol.
A goal by Joan Verdu gave the visitors the lead towards the end of a first half which saw few chances and little incident or excitement.
The hosts failed to produce the commanding performance coach Luis Garcia had demanded before the game, and their level dropped even further when Borja Fernandez was sent off early in the second half.
Getafe centre-back Federico Fernandez then also received his marching orders midway through the second period before Espanyol midfielder Christian Stuani made sure of the points immediately after with his side's second goal.
Osasuna could not get the win they needed to arrest a poor run of form that has them hovering just above the relegation zone, but did enough to frustrate Real Sociedad's European ambitions in a disappointing goalless draw in Pamplona.
There were desperately few chances of note at either end, although Sociedad's Imanol Agirretxe was denied by a post midway through the first half with a header from a corner.
Fernando Llorente scored his first Primera Division goal since September to earn 10-man Athletic Bilbao a 1-1 draw from their trip to in-form Deportivo La Coruna.
Bruno Gama had Depor dreaming of a fifth successive victory with his 38th-minute strike but Llorente headed Athletic level just before the break to earn a point for the Basque outfit, who were forced to hold on with a man less for the final nine minutes following the dismissal of Ander Iturraspe.
Information from the Press Association was used in this report.