After claiming a hard-fought victory against Manchester United in the UEFA Champions League in midweek, Atleti showed no signs of tiring as they went straight onto the front foot here in Barcelona.
Lee Kang-in blazed over from just a few yards out after Jonathan David neatly laid the ball into his path, before the Canadian himself latched onto Giuliano Simeone’s pass into the danger area and sent a shot narrowly over the bar.
Espanyol soon began to gain a foothold as the contest settled, but they lacked a cutting edge in the final third.
It took until just after the half-hour mark for the hosts to go close to an opener with a well-worked corner which caught Atleti cold in defence, but Bryan Zaragoza’s cross was headed inches wide by Roberto Fernandez.
David was then denied by Angel Fortuno, who did well to palm the ball onto the right post, before Leandro Cabrera ran onto a loose ball at the edge of the box and crashed his strike off the crossbar to close out the half.
Unhappy with his side’s first-half performance, Simeone made a double change ahead of the restart, with Ademola Lookman one of the players replaced.
Both teams struggled and looked lethargic in the opening quarter-hour of the second half, with neither goalkeeper tested. Marcos Llorente did have Fortuno scrambling in the 62nd minute when he struck from distance, but with the goalkeeper beaten, he was only denied by the crossbar.
Fortuno was again tested with a shot from distance, this time from Julian Alvarez, whose powerful strike from 25 yards out was tipped over the bar, while Morten Hjulmand headed into the side netting from the resulting corner.
Atleti were pushing for the breakthrough, and just as it looked like Espanyol had done enough to hold on and secure a point, Los Colchoneros broke the deadlock in the 89th minute.
Alvarez cut inside from the left and picked out Baena outside the box, and the Spaniard took a touch before picking his spot in the left corner.
That secured a victory which helps Atletico keep pace with leaders Barcelona, while Espanyol suffer a third defeat in four games.
Flashscore Man of the Match: Cristian Romero (Atletico Madrid)