Espanyol stunned Barcelona, 3-1, in the city derby match on Saturday to dent the Primera Liga title hopes of the reigning Spanish champions.
Luis Garcia's opened the scoring for Espanyol only for striker Javier Saviola to equalize for the champions.
However, strikes from Raul Tamudo and Rufete sealed the win for the hosts with Barca missing the chance to go on top of the Primera Liga.
The game started at a frenetic pace and it was Espanyol who had the first attempt on goal. Ivan De La Pena whipped a dangerous free kick into the box, but Tamudo could not connect and Victor Valdes gathered.
After six minutes, De La Pena went down on the edge of the area under a challenge from Rafael Marquez, but referee Arturo Ibanez correctly waved play on. Albert Riera then fired a low drive just wide as Espanyol began to dominate.
But Ronaldinho, playing his first game of 2007, came within a whisker of the first goal after 10 minutes. The Br azilian, jeered throughout by the home fans, curled an exquisite free kick on to the bar.
Juliano Belletti then tried to surprise Carlos Kameni in Barcelona's next attack, but the Cameroon goalkeeper dived low to save. At the other end, Rufete saw a similar effort stopped by Valdes.
Espanyol then almost scored after 29 minutes, when De La Pena put Rufete through with a delightful long pass, but the Spanish midfielder shot into the side netting. A minute later, Espanyol went ahead. Tamudo skipped past Belletti and squared for the unmarked Luis Garcia, who netted from close range.
Tamudo could have doubled Espanyol's lead after 38 minutes, but headed straight at Valdes. The Espanyol captain popped up again two minutes later but took too long to shoot.
Barcelona coach Frank Rijkaard sent on Saviola for Giuly at halftime and the Argentine equalized after 59 minutes. Saviola, fed by Eidur Gudjohnsen 30 yards out, skipped past two defenders before beating Kameni with a low shot.
Tamudo had just wasted a great chance to put Espanyol two ahead, but the striker made up for his error after 65 minutes, when he headed the home side back ahead as Rijkaard punched the side of the dugout in disgust.
Barcelona piled forward in search of an equalizer, but left spaces at the back and Espanyol killed the game off with a deserved third goal at the death when Luis Garcia squared unselfishly for Rufete to score.
Valencia moved up to third in the Primera Liga with a 3-0 victory over neighbors Levante in the city derby.
Quique Sanchez Flores' men took control of the game in the second half with goals from substitute Hugo Viana and Fernando Morientes before defender Roberto Ayala added a late third.
The win confirms that Valencia is well in contention for the Primera Liga title despite a first half of the season when they were plagued by injuries, sometimes having to field what was, in effect, a reserve team.
Levante, meanwhile, slip closer to the relegation zone and the defeat will put pressure on coach Juan Ramon Lopez Caro, who had been given some respite by last week's 2-0 victory over Racing Santander.