Valencia ended Real Madrid's 22-game winning streak by fighting back for a 2-1 victory on Sunday that throws open the Spanish league title race.
Cristiano Ronaldo extended his stunning tally to 26 league goals in the 14th minute at Mestalla Stadium when he stroked in a penalty kick following Alvaro Negredo's handball.
But the hosts rallied through a goal by Antonio Barragan in the 52nd before defender Nicolas Otamendi fended off Sergio Ramos to head home the 65th-minute winner.
Madrid still has a game in hand, but Barcelona can take the provisional lead with a win at Real Sociedad later. Defending champion Atletico Madrid was also left one point behind the pacesetters.
Valencia's first win in six visits by Madrid lifted it into fourth place.
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