Madrid - Real Madrid suffered their first defeat on Sunday, 2-1 away to spirited Sevilla, who now share second place with them. Jesus Navas gave Sevilla the lead, Pepe levelled for Real - but then Renato headed in the winners for the hosts.
The well-deserved win confirms that Sevilla are determined to stop Real and Barcelona from enjoying another two-horse race.
"It was really crucial for us to win today," said Renato, "in order to show that we can battle for the title."
Real's Gonzalo Higuain said that "they played well tonight, though we could have got a draw here."
Sevilla and Real both have 15 points from six games and are three behind leaders Barcelona, who on Saturday made it sixth wins in six by beating Almeria 1-0.
Real sorely missed Cristiano Ronaldo, absent with a twisted right ankle.
Sevilla dominated the first half and made Real keeper Iker Casillas work hard. In the 33rd minute little Navas got in front of Marcelon and made it 1-0 by heading in a centre from the left from Fernando Navarro.
Four minutes into the second half Real equalized, against the run of play, when Pepe headed in a free-kick from veteran Guti.
The visitors seemed capable of turning the tables, as they did last season in the Sanchez Pizjuan, but in the 66th minute Renato made it 2-1 by heading in a centre from Adriano, following a clever corner.
There was no way back this time for Real, and Sevilla wasted good chances to increase their lead at the end.
Earlier on Sunday Valencia had moved up to fifth with a tight 1-0 win away to Racing Santander, on a late goal from supersub Zigic.
The towering Serbian had only been on the field for five minutes, after league top scorer David Villa had limped off with a torn muscle in his right thigh.
Villa will almost certainly miss Spain's final World Cup qualifying games against Armenia and Bosnia.
In the 61st minute Santander veteran Pablo Pinillos played a terrible back-pass for goalkeeper Tono and Zigic powered in to score.
Santander pushed hard for a draw at the end but the Valencia defence - which has already leaked 12 goals this season - this time stood firm.
"It was an important win for us," said Valencia captain Carlos Marchena, "because our recent results have not been very good."
Marchena and company are now fifth with 11 points from six games. They are one point behind Deportivo Coruna and one above Mallorca and Athletic Bilbao.
Earlier on Sunday Mallorca were thrashed 4-1 by Sporting Gijon, for whom Miguel de las Cuevas scored two goals.
Bilbao, for their part, battled out a 2-2 draw in Valladolid, thanks to a late equalizer from Iker Munain.
One point behind Bilbao and Mallorca are Getafe, who beat Osasuna 2-1 on a late goal from Pedro Leon.
Villarreal coach Ernesto Valverde, meanwhile, is in massive danger after his troubled team were held to a 0-0 home draw by Espanyol, who played with 10 men for most of the game.
Villarreal - who reached the quarter-finals of the Champions League last season - are now second from bottom of La Liga without a win to their name, with just three points from six games.
"We really should have won today," said Villarreal striker Guiseppe Rossi, "but we didn't take our chances."
In the 15th minute Espanyol defender Juan Forlin was sent off for pulling down Rossi. However, the out-of-form Villarreal defence failed to break down the weakened Espanyol defence.
Valverde - who, ironically, enjoyed his best coaching days at Espanyol - is likely to become the first Liga coach sacked this season.
Sunday's other early game was a tense 1-1 draw between bottom team Xerez and Malaga, who are third from bottom.
