Sergio Aguero’s late goal helped Atletico Madrid come from behind to beat Barcelona 4-3 and blow the Spanish title race wide open.
Barcelona,who led 2-0 and 3-2,have now failed to win in four matches and have seen their lead over Real Madrid cut from 12 points,just three weeks ago,to four.
Thierry Henry put Barcelona ahead with a fine strike from 25 yards which flew into the top corner after 18 minutes before Lionel Messi,on the half-hour mark,produced a trademark dribble before finishing in style.
Diego Forlan brought Atletico back into the match with a spectacular 30-yard drive before Aguero got the first of his brace after 56 minutes.
Barcelona,who were stunned by struggling Espanyol last weekend,re-established their lead when Eidur Gudjohnsen unselfishly played in Henry for his second from close range in the 73rd minute.
But Atletico were not finished and Forlan again scored,this time from the penalty spot in the 80th minute,before Aguero struck in the 89th minute to win the match.
Meanwhile,the pressure is growing on Valencia coach Unai Emery as his side followed their mid-week UEFA Cup elimination with a 2-1 home defeat by Valladolid.
After a bright start to the season,Valencia have tumbled to sixth in the table and have now gone more than a month without a win.
It took just six minutes for Valladolid to go ahead with Jonathan Sesma heading home but then chances came and went for both sides before Raul Albiol scored an own goal to double the lead.
Valencia continued to create openings but missing David Villa through suspension they lacked a finishing touch.
They did eventually manage to find the back of the net through Carlos Marchena after 73 minutes but it was only to be a consolation.
Malaga’s hopes of European qualification suffered a setback when they were beaten 2-0 at home by mid-table Recreativo Huelva.
The Andalusian side have surpassed expectations this season but after the first-half dismissal of Manuel Lolo they struggled against Recreativo.
Javier Camunas gave the visitors the lead after 54 minutes with a shot from the edge of the area and then Jesus Vazquez hit the post before they doubled the lead with a fine finish from Adrian Colunga.
Deportivo La Coruna are just below seventh-placed Malaga on goal difference after they beat bottom side Numancia with a Juan Rodriguez strike mid-way through the second half.
Mallorca continued their fight against relegation by beating Sporting Gijon to secure their third successive win with a free-kick from Juan Arango to giving the visitors the win.
A Walter Pandiani goal in first-half injury time rescued a point for Osasuna who drew 1-1 with Racing Santander but they are still encamped in the bottom three.
On Saturday,Real Madrid reduced the gap on Barcelona when substitute Guti and veteran skipper Raul scored in a 2-0 win at Espanyol.
Real coach Juande Ramos singled out Guti for praise.
“We knew that the game was not going to be easy but we were very motivated,” said Ramos,whose team had been stunned by a home midweek Champions League defeat to Liverpool.
“There was little difference between the teams in the first half but after the break Guti changed the match and after his goal Espanyol had to take risks which led to the second goal.”
A Frederic Kanoute brace helped Sevilla come from behind to beat Athletic Bilbao,who had gone ahead through Inaki Gabilondo,in a dress-rehearsal of the Copa del Rey semi-final on Wednesday. It consolidated Sevilla in third but still 13 points behind leaders Barcelona.