Veteran French striker David Trezeguet scored twice as promoted Hercules took another big league scalp defeating Sevilla 2-0 on Sunday.
Hercules caused the sensation of the season when they beat champions Barcelona 2-0 a fortnight ago and followed that by downing Sevilla, regulars on the Champions League circuit and fourth last season.
It was a first league defeat of the season for Sevilla who lie sixth, five points off leaders Valencia with Hercules now just a point behind them.
A World Cup winner with France in 1998, Trezeguet struck a penalty on 21 minutes to put Hercules ahead and grabbed a second on 38 minutes after great work from Dutch midfielder Roysten Drenthe who is on loan from Madrid.
Trezeguet, 32, has now scored three times for Hercules having made a surprise free transfer move to the league newcomers after a decade with Italian giants Juventus.
The loss means more pressure for Sevilla coach Antonio Alvarez who saw his team crash out of the Champions League qualifier to Braga and lost 1-0 to Paris Saint Germain in their opening Europa League match.
"While I am in charge I will give the maximum 24 hours a day," said Alvarez.
"The team didn't lack commitment. Sometimes the desire is there but things don't turn out well."
Elsewhere Atletico Madrid moved above Sevilla and up to fourth with a 1-0 victory over Real Zaragoza at the Vincente Calderon.
Atletico had collected one point from the last six but got back to winning ways with Brazilian debutant Filipe Luis - a 12-million-euro signing from Deportivo La Coruna - setting up Diego Costa for the winning goal on 20 minutes.
Atletico sit three points behind pacesetters Valencia while Zaragoza have yet to win and prop up the table.
Earlier Espanyol maintained their 100 percent home record with a 1-0 victory over 10-man Osasuna at the Cornella El Prat Stadium to go sixth in the Spanish top-flight.
Osasuna had to play 69 minutes of the match with one man fewer after defender Manuel Lolo was sent off on 21 minutes for a second yellow card and Espanyol went in front three minutes later through Alvaro Vazquez.
Espanyol, beaten 3-0 at Real Madrid on Tuesday, could not extend their advantage but held on to make it three wins out of three and move sixth two points behind third-placed Real Madrid.
In other matches, Almeria won their first game of the season with a brace from Nigerian striker Kalu Uche ensuring a 2-0 win over 10-man Deportivo La Coruna 2-0 at the Riazor stadium.
Uche scored a quick-fire double, after four and 18 minutes, to put Almeria in control and Depor were reduced to ten men shortly before half-time when Argentine defender Diego Colotto was given a straight red card for hauling down compatriot Pablo Piatti.
Depor are yet to win this season and sit second from bottom of the table after scoring just two goals in their first five league matches.
In other matches, Real Mallorca defeated newcomers Real Sociedad 2-0 at home thanks to a brace from Fernando Cavenaghi.
Argentine striker Cavenaghi struck in the fifth and 62nd minute as Mallorca continued their unbeaten home record and have collected all seven of their points in front of their own fans.
Valencia are the new league leaders after defeating Sporting Gijon 2-0 on Saturday to make it 13 points from a possible 15 and lie a point ahead of second-placed Barcelona.
Barcelona triumphed 3-1 at 10-man Athletic Bilbao on Sunday to move above rivals Real Madrid who drew 0-0 with Levante on Sunday to fall to third two points behind leaders Valencia.
On Monday Villarreal can move a point behind Valencia if they can notch a fourth successive league victory at Malaga.
