Real Madrid's bid for a record 17th consecutive LaLiga victory fell short as Villarreal held them to a 1-1 draw at the Santiago Bernabeu.
Cristiano Ronaldo and Gareth Bale were back in Zinedine Zidane's XI for their tilt at history, but had little joy during an opening half that ended with Bruno Soriano putting the visitors ahead from the penalty spot.
Sergio Ramos was culpable for his team falling behind, but quickly atoned by heading home from James Rodriguez's 48th-minute corner.
Karim Benzema, Bale and Ronaldo all went close to inking Madrid's latest entry into the history books, but their 16-match run, which began after February's derby defeat to Atletico Madrid, puts them level with the mark set by Pep Guardiola's Barcelona during the 2010-11 season.
Zidane's men remain top of LaLiga despite losing their 100 per cent record this term and Barca and Atleti will look to close the gap when they meet at Camp Nou later on Wednesday.
Mateo Kovacic returned to the Madrid XI alongside their superstar forwards as a result of the calf injury Casemiro suffered against Espanyol, and much of the early action was concentrated in the midfield area as Villarreal kept their illustrious opponents at arm's length.
In the 19th minute, Sergio Asenjo swatted the ball to safety after Karim Benzema sought to turn in Bale's header back across goal.
Fran Escriba's side were playing with the confidence of a team on a three-match winning run and Kiko Casilla was forced to push a drive from ex-Madrid midfielder Denis Cheryshev behind before Nicola Sansone sliced an elaborate volley from the resulting corner.
Ronaldo was largely starved of service and was penalised for a foul when getting on the end of a Marcelo centre before firing an ambitious long-range effort off target in the 32nd minute.
The similarly peripheral Bale followed suit five minutes later and, after Marcelo limped off to be replaced by Dani Carvajal, a forgettable half for the hosts concluded with Ramos handling Samu Castillejo's shot just inside the area and Bruno floating a Panenka spot-kick into the net.
Ramos led from the front from the restart, seeing an effort blocked when Asenjo fumbled a corner before picking out the bottom corner from a subsequent set-piece.
Benzema glanced wide afterwards as Madrid attacked their opponents with an intensity entirely lacking from their first-half work.
The French striker turned provide when Ronaldo narrowly failed to turn home a dangerous low cross and Bale steered a side-footed effort past the post in the 65th minute as Madrid continued to crank through the gears.
An exasperated Ronaldo was booked for a late challenge on Bruno before Bale made way for Lucas Vazquez inside the final 20 minutes.
Another header was guided off target by Benzema and the Frenchman made way for Alvaro Morata, but there was no way through despite Zidane utilising his full array of forward options.
Morata did come close by steering a header into the turf that brought a stunning reaction stop from Asenjo, who might have been facing a penalty had Bruno's clumsy late challenge on Ramos brought anything more than unanswered fury from the stands.