Espanyol striker Walter Pandiani secured a 1-1 draw in stoppage time to extend Real Betis' winless streak to five games.
After a poor first half Ruben Castro had headed the hosts in front from Michael Pereira's cross with 18 minutes remaining.
Didac Vila looked to have wasted the chance to get Espanyol back into the game as he missed a great opportunity, but just as when these two met in October, Pandiani came off the bench to make a telling contribution as he took advantage of some slack Betis defending to volley home from just inside the area.
The visitors had enjoyed two days less rest than Betis and that must have affected Mauricio Pochettino's preparation for the match as he made six changes to the side that beat Racing Santander on Monday night.
However, Espanyol still enjoyed the better of the play in the first half and squandered the only real chance as Philippe Coutinho cut inside on to his right foot but pulled his effort from the edge of the area wastefully wide.
Betis provided more of an attacking threat after half-time and Benat Etxebarria also passed up a good shooting opportunity as he dragged the ball wide four minutes after the break.
Espanyol were still being restricted to long-range shots at goal but they were unfortunate not to take the lead on two occasions midway through the half as another Coutinho effort flew just over the crossbar before Ndri Romaric drove a free-kick inches past the post.
It was Betis though who made the breakthrough as Pereira's cross from the right found Castro in acres of space inside the area and the striker did not even need to jump as he guided the ball past Kiko Casilla from close range.
Romaric saw another shot parried from Fabricio before a lovely through-ball from Coutinho played Vila in on the left side of the box, but the full-back lacked the composure needed in front of goal as he could only fire into the side-netting.
Espanyol did though eventually get the equaliser their performance deserved in stoppage time as a mix-up between Paulao and Nelson allowed Javi Lopez's pass to reach the feet of Pandiani and the Uruguayan made no mistake with a shot that rocketed into the top corner.
The draw means that Espanyol move back into the European places in sixth, whilst Betis are now seven points clear of the relegation zone in 15th.
