Leganes produced the shock of the season on Sunday night when the side that won promotion to La Liga last season won 1-0 away to FC Barcelona.
Sergio Gonzalez headed in the only goal of the game in the fourth minute after he was left completely unmarked after a corner, and from then, Leganes held on with some last-ditch defending and some incredible saves from goalkeeper Marko Dmitrovic.
Dmitrovic produced two fine saves in the first half to deny Robert Lewandowski and an even better stop to tip Raphinha's shot onto the woodwork.
Barcelona had 80 percent of the ball but failed to find a way through and is now level on points with Atletico Madrid. They will also be worried after Lamine Yamal seemed to pick up another ankle injury in the first half, although he played on until the 75th minute.
Atletico Madrid moved into second place above Real Madrid after a hard-fought win at home to Getafe, which was decided by Alexander Sorloth's towering header that gave Getafe goalkeeper David Soria no chance of making a save.
Giuliano (L) of Atletico de Madrid vies with Coba Gomes of Getafe CF during the La Liga football match between Atletico de Madrid and Getafe CF in Madrid, Spain, on Dec. 15, 2024. (Photo by Gustavo Valiente/Xinhua)
Real Madrid missed the chance to go top for 24 hours after a thrilling 3-3 draw away to Rayo Vallecano on Saturday night.
Unai Lopez and Abdul Mumin put Rayo 2-0 up with goals after four and 35 minutes, but Madrid was level before the break through Fede Valverde and Jude Bellingham.
Rodrygo fired Madrid 3-2 up in the 55th minute, but Rayo fought back and leveled when Isi Palazon directed Florian Lejeune's shot past Thibaut Courtois in the 63rd minute, with Rayo defending well to claim a point.
Athletic Club Bilbao saw their six-game winning streak come to an end with a 1-1 draw in their Basque derby away to Alaves on Sunday afternoon.
Unai Gomez put Athletic ahead early in the game, and the visitors rarely looked in trouble until Unai Simon, making his first start of the season in La Liga after a wrist operation in the summer, failed to hold Jon Guridi's second-half shot through a crowd of players, allowing Joan Jordan a simple finish.
Villarreal failed to close the gap on Athletic after sliding to a 2-1 defeat at home to Betis, who played for almost an hour with ten men after Chimy Avila was sent off for a wild challenge on Alex Baena in the 34th minute.
Vitor Roque had given Betis the lead a minute before Avila's red card and Giovani Lo Celso doubled their advantage early in the second half. Baena scored for Villarreal in the 55th minute, but the home side couldn't find an equalizer.
Real Sociedad also dropped points at home after a 0-0 draw to an improving Las Palmas, in a game where Real Sociedad had more of the ball, while Las Palmas had slightly better chances.
Sevilla legend Jesus Navas had a winning goodbye to the Sanchez Pizjuan Stadium as the player with over 700 games for the club hung up his boots after a 1-0 win at home to Celta, with Marco Bueno scoring a second-half winner.
Cyle Larin scored twice as Mallorca played for an hour with ten men, but still beat Girona 2-1.
Donny Van de Beek volleyed Girona ahead six minutes before Vedat Muriqi set up Larin's equalizer, shortly before seeing red for a bad challenge on Bryan Gil.
Larin rewarded Mallorca's courage when he charged down Paulo Gazzaniga's attempted clearance, and the ball cannoned into the net.
Espanyol and Osasuna drew a poor game 0-0, while Valencia coach Ruben Baraja is facing the sack after his side lost 1-0 to Valladolid on Friday night, with Anuar Tuhami scoring the only goal of the game after 19 minutes.
Valladolid hung on for the win with ten men after Juan Latasa was sent off with 13 minutes left to play.