Real Madrid were left shell-shocked by a clever last-gasp Pablo Fornals goal as Villarreal earned a smash-and-grab 1-0 win at the Santiago Bernabeu.
LaLiga's champions largely dominated proceedings on home soil, but Villarreal snatched all three points and a first league victory at Madrid with three minutes left thanks to Fornals' exquisite chip after Enes Unal's shot was saved.
It compounded a day of utter frustration for an out-of-form Madrid, who felt they twice should have had a penalty in the first half.
Villarreal defender Alvaro Gonzalez was lucky to not face punishment for handball from a Gareth Bale header, while Cristiano Ronaldo was adamant he was fouled by Mario Gaspar on the stroke of half-time.
Referee Alberto Undiano Mallenco was unmoved on both occasions, while Madrid were further frustrated by a poor one-on-one miss by Ronaldo and some good work by Villarreal goalkeeper Sergio Asenjo.
Madrid have now won just once in five LaLiga matches and will be 19 points adrift of Barcelona if their Clasico rivals beat Real Sociedad on Sunday, while Villarreal are just one point adrift of Los Blancos in their bid to muscle in on the top four.
Isco saw an early effort blocked by Gaspar, with the Spain playmaker's tentative penalty claims for handball rightly going unheard.
Bale saw a goal ruled out after nodding in from Ronaldo's header back across goal, before Asenjo made a fine stop from Marcelo's rasping 35-yard drive.
He made an even better stop to palm Ronaldo's 25-yard dipping free-kick over the top via the crossbar, before the Portugal captain wastefully dinked over Asenjo and wide of the left post after latching onto Luka Modric's throughball.
Ronaldo went close again shortly after when he hit a stinging drive into the side-netting.
Madrid were unfortunate not to be awarded a penalty 10 minutes before half-time when Bale's header from Toni Kroos' left-wing cross was seemingly handled by Alvaro Gonzalez. And Madrid had more cause for consternation on the stroke of half-time.
Isco's teasing low cross was met by Ronaldo inside the six-yard box and saved brilliantly by Asenjo, but the forward was seemingly clipped by Gaspar when meeting the ball.
Villarreal brought Denis Cheryshev on as a half-time substitute and the former Madrid winger picked Casemiro's pocket before dragging wide from the edge of the box.
A lively start to the half saw Raphael Varane make a crucial intervention from Samu Castillejo's probing pass, while Asenjo was equal to a well-controlled Kroos volley.
Modric saw a 20-yard daisycutter well held by Asenjo, while the Croatia midfielder hit a fierce drive over the top from outside the area with 10 minutes remaining.
And Madrid were made to rue their lack of clinical edge in the 87th minute.
Villarreal launched a lightning counter-attack led by Cheryshev, who slipped in Unal and, although his shot was saved by Keylor Navas, Fornals was on hand to brilliantly clip his shot over the stranded Madrid goalkeeper to spark jubilant scenes on the away bench.
Key Opta stats:
- Real Madrid attempted 28 shots against Villarreal, the most for a team in a LaLiga game this season.
- Villarreal have won for the first time in their 18 league visits to Santiago Bernabeu (D5 L12)
- Isco has been substituted more times than any other Real Madrid player in LaLiga this season (10)
- Real Madrid have not won in five home games in LaLiga this term (D2 L3), the same as in the whole of last season (D4 L1) and more than in any other LaLiga season since 2006-07 (D4 L3).
|Federer maintains perfect Australian Open second-round record|
|Warriors set NBA record, Butler´s 76ers rout Timberwolves|
|´I like the fact we beat them´ - 76ers´ Butler revels in win over Timberwolves|
|Murray says he´ll ´probably´ have operation|
|Australian Open tribute for Andy Murray surprises brother Jamie|
|Warriors score NBA record 51 points in first quarter against Nuggets|
|Panthers owner Tepper doesn´t rule out Newton missing 2019 because of shoulder injury|
|De Ligt will be world´s best centre-back – Koeman|
|Ronaldo a ´perfect machine´, says Gattuso|
|Barcelona? I can´t say anything - Stuani|
|Silva upbeat about Man City title chances|
|Celtics youngsters say Irving´s callout ´came from a good place´|
|NFL playoffs: Patrick Mahomes v Tom Brady|
|NFL playoffs: Jared Goff v Drew Brees|
|Sixers sign Brewer to 10-day contract|
|Lozano and Morgan scoop CONCACAF awards|
|Lakers ´optimistic´ about LeBron injury|
|Giants produce mammoth fourth quarter against Nymburk|
|Austin FC to join MLS in 2021|
|Henry, Vieira look forward to reunion when Monaco host Nice|
|Barcelona reject Neymar phone call reports|
|Wentz is the quarterback ´going forward´, says Eagles coach Pederson|
|Gattuso: Higuain has not asked to leave|
|Drew Brees by the Opta numbers: 10 facts for QB´s milestone birthday|
|Harry Kane injury: England captain´s history of ankle woe|
|Harry Kane injury: Opta numbers suggest Spurs struggles|
|Harry Kane injury: Tottenham´s options in striker´s absence|
|Allegri: Supercoppa clash practice for Champions League knockouts|
|First in clean sheets, second to Schmeichel in titles – Cech´s Premier League career in Opta numbers|
|Warrington sign England star Widdop|
|Gatland confident Wales can win Six Nations|
|Fulham sign Netherlands international Babel|
|Harry Kane injury: Games the Tottenham striker will miss|
|Simeone focused on matches, not transfer dealings|
|Iran v Iraq: Pressure off for Queiroz & Katanec|
|Vietnam v Yemen: Kocian keeps the faith|
|Darren Bravo back in West Indies Test side for first time since 2016|
|Kane out until March with ankle injury|
|South Korea v China: Son arrives for Group C dead rubber|
|Kyrgyzstan v Philippines: Eriksson remains hopeful|
|McGrath to miss Six Nations, Sexton nearing fitness|
|Kohli savours Dhoni ´classic´|
|Ford: People obsess over Farrell fly-half battle|
|EFL asks Leeds to explain ´spygate´ scandal|
|No alarms for Djokovic and Zverev, Raonic masters Kyrgios|
|Australia 3 Syria 2: Rogic breaks hearts with stoppage-time winner|
|Palestine 0 Jordan 0: Socceroos winner keeps hopes alive for Lions of Canaan|
|Halep: The results don´t matter any more|
|Hard work for Halep as Serena and Osaka sail through|
|Napoli director to take legal action over ´false´ quotes about Rog move|
|Alexander-Arnold facing absence of up to four weeks|
|Solari: We only have one number nine at Real Madrid|
|Halfpenny & Young named in Wales´ Six Nations squad|
|Crawford v Khan confirmed for April 20|
|Centurion Kohli inspires India to level ODI series|
|Wagner hails Huddersfield togetherness after exit|
|Hughes to join Bristol, Le Roux also leaving Wasps|
|ICC appoints Sawhney as new CEO|
|Forest appoint club legend O´Neill as new manager|
|Halep digs deep to gain revenge over Kanepi|
|Cech to retire at the end of the season|
|Brisbane Roar 0 Melbourne Victory 5: Barbarouses treble sinks Roar|
|´Struggling´ Azarenka breaks down in tears following Australian Open exit|
|Dominant Djokovic coasts through in Melbourne|
|Allardyce admits Huddersfield appointment is ´highly unlikley´|
|Choupo-Mouting: Manchester United have changed|
|Faletau set to miss Six Nations with another broken arm|
|UEFA opens disciplinary proceedings into Chelsea chants|
|Serena´s the greatest ever - Bouchard relishing second-round clash|
|Mbappe can become the new Pele - Pele|