Diego Simone's lacklustre Atletico Madrid finally surrendered their unbeaten league record to a well taken Sergio Garcia strike late in the game, in a contest that was short on quality throughout.
Each side came into the fixture in contrasting form. Atletico had won five of their last six Primera Division games, winning the last four and looking the most likely team to challenge Barcelona's supremacy at the summit of the league. The hosts have had a season of struggle so far, languishing in 16th and only one of the previous six league matches and creeping ever closer to the bottom three.
Espanyol made two changes from the team that drew 2-2 away at Las Palmas, with Javi Lopez and Javi Fuego starting. For the visitors, Fernando Torres started in place of French striker Kevin Gameiro after coming off the substitutes' bench to score the late winner against Alaves.
In front of a sparse crowd, Atletico took control of the early stages of the game dominating possession without duly troubling Espanyol goalkeeper Pau Lopez.
Much of the initial stages of match was being played in the midfield area, but Espanyol were gradually growing in confidence and creating opportunities down Los Indios' left flank with Aaron Martin looking threatening.
The first real chance was created by the hosts in the 19th minute when Sergio Garcia made an incisive break and played in Leo Baptistao, as Jan Oblak advanced off his line the former Atletico player tried to chip the on-rushing goalkeeper from the edge of the area only to see his tentative effort go wide and the golden opportunity to take the lead was lost.
Espanyol began to gain momentum, with David Lopez's speculative effort from 20 yards comfortably tipped over the bar by Oblak to force another corner which ultimately came to nothing.
The most contentious incident of the half came when Torres quickly closed down an attempted clearance by Javier Lopez , delivering the ball to Antoine Griezmann to round the home keeper.
Lopez bravely dived at the striker's feet in an attempt to collect the ball, however the French international blatantly dived to entice the foul, but the referee was not to be fooled and rightfully gave a goal kick - although the official decided against booking the striker for simulation.
A tightly fought half eventually drew to a close with Espanyol content to be on level terms. The visitors had lost their early impetus and they seemed the team satisfied to absorb the pressure and grind down their opponent.
The second half started very much like the first with Atletico looking to dominate possession and force Magico to retreat. However Espanyol were proving collectively resilient allowing Simeone's men to retain the ball, then they would defensively spark into life when the visitors dared to enter the final third of the pitch.
The game was not able to flow with the continual break up of play through petty free kicks and neither keeper being troubled. Then in the 68th minute, Moreno retrieved the ball on Atletico's byline and crossed smartly for Garcia to take a first time shot which went agonisingly wide of Oblak's near post.
In the 77th minute a terrifically weighted pass by Griezmann from midfield freed countryman Gameiro, a second half substitute. Unfortunately, the striker shot straight at Lopez while heavily under pressure from the hastily tracking home defenders.
The winner came late on when Espanyol substitute Esteban Granero broke down the right side of the penalty area and crossed towards the on-rushing Garcia who, without breaking stride, calmly passed the ball past the stationary Oblak to send the home supporters wild in celebration as they claimed all three points in a hard fought contest.