Real Madrid were held for the second La Liga game in a row as Las Palmas twice came from behind to claim a 2-2 draw in Gran Canaria.
Zinedine Zidane's men had seen their club-record run of 16 straight La Liga wins ended at home to Villarreal in midweek and their lead at the top has now been cut to one point, with Barcelona having beaten Sporting Gijon 5-0 earlier on Saturday.
Marco Asensio gave Real a 33rd-minute lead but Tana quickly cancelled it out to leave the teams level at the break.
Substitute Karim Benzema fired in a rebound to restore Real's lead in the 67th minute but Las Palmas' encouraging start to the season continued as Sergio Araujo took advantage of a lucky ricochet to level with five minutes left.
Las Palmas goalkeeper Javi Varas was called upon in the eighth minute to tip Alvaro Morata's close-range header over the bar after Toni Kroos had floated in a set-piece from the left.
Cristiano Ronaldo chested down a Luka Modric pass and volleyed wide with a quarter of an hour gone, and the Portuguese and Morata had further efforts blocked at close range by the massed ranks of Las Palmas defenders in the 24th minute after Dani Carvajal's low ball across the six-yard box.
Real got the breakthrough in the 33rd minute when Varas' clearance was well read by Nacho, who made a forceful burst forward into the box. His angled drive was parried on the stretch by Varas but Asensio was on hand to nod in the rebound from six yards.
The lead was short-lived, though, as Momo's cross from the left was only headed out by Raphael Varane as far as Tana, who steadied himself before placing a left-foot shot low to Kiko Casilla's right.
Varas got his body behind a Gareth Bale half-volley with two minutes of the half remaining after a cross-field pass put him away down the right, but it was honours even at the break.
Real were quickest out of the blocks in the second period as Ronaldo squared the ball from the left to Bale, whose shot from the outer edge of the D was parried away by Varas.
Ronaldo was correctly called offside from Bale's pass as he stepped past Varas and slotted one in and at the other end Michel fired over after neat interplay down the right with Nabil El Zhar as the game entered the final 30 minutes.
The 'BBC' triumvirate was reunited as Benzema came on for Asensio in the 64th minute, and he had a half-chance to score with his first touch when the ball arrived at him quickly in the box after Varane had flicked on a corner.
But the Frenchman did get on the scoresheet three minutes later as he followed up to score after Varas had blocked Ronaldo's effort following an eye-of-the-needle pass from Morata.
Ronaldo's celebration of the goal was very much on the muted side and he looked none too impressed when Zidane took him off for Lucas Vazquez with 18 minutes left, with an important Champions League tie away to Borussia Dortmund coming up.
The hosts had put in a determined performance and secured a point when Tana crossed from the left and Vicente Gomez cushioned a header into the path of Araujo.
The Argentinian's initial effort was blocked by Casilla but the ball ricocheted goalwards off Araujo and he completed the job by tapping in on the line.
Benzema skied a volley and fellow sub Isco headed over as Real wasted chances to win it in injury time.