The Andalusian side were briefly knocked off the top by Valencia - but they defeated Getafe 3-2 to reclaim pole position.
Getafe led 2-1 in the 88th minute to go courtesy of goals from Pedro Leon and substitute Nicolas Fedor Miku, either side of Ruud van Nistelrooy's equaliser.
But Enzo Maresca tapped in a scruffy equaliser, before Julio Baptista won it with a stunning overhead kick.
Sergio Canales' fine early goal was sufficient to seal victory for Valencia over Granada, although forwards Roberto Soldado and Jonas Goncalves wasted a hatful of chances to extend the lead.
Villarreal's disappointing start to the season continued as they were held at home by 10-man Real Zaragoza, needing a late equaliser to avoid defeat.
The visitors twice took the lead at El Madrigal, Luis Garcia opening the scoring in the 34th minute and Pablo Barrera restoring their advantage on the stroke of half-time after Giuseppe Rossi had equalised.
The dismissal of Zaragoza defender Maurizio Lanzaro gave Villarreal a boost and substitute Hernan Perez salvaged a point with an 83rd-minute leveller.
The result leaves Juan Carlos Garrido's side, who were fourth last season, with just one win from their opening six matches.
Raul Garcia and Tomer Hemed both scored twice as Osasuna and 10-man Real Mallorca shared the points in an entertaining encounter at the Reyno de Navarra stadium.
Hemed scored his first goal for the visitors from a penalty on 34 minutes after Miguel Flano had felled the Israeli just inside the area.
Garcia then headed the hosts level in first-half injury-time and he repeated the trick 15 minutes into the second period to give his team the lead.
Mallorca were reduced to 10 men in the 72nd minute as Emilio Nsue was shown a straight red card for kicking out at Roland Lamah, but they were given a second penalty minutes later as Lamah appeared to clip the heels of Alejandro Alfaro and Hemed stepped up again to claim a point for his side.
In Saturday's other game, substitute Adrian scored Racing Santander's first goal since the opening weekend to claim a 1-1 draw with visitors Rayo Vallecano, who had led through Raul Tamudo's goal.