The Brazilian midfielder's first goal for the club came off a corner two minutes after the home side's Willian Jose had equalised after a misplaced pass from Madrid substitute Mateo Kovacic.
Barcelona beat Getafe 6-0 on Saturday and are eight points clear of Atletico.
Sergio Ramos's flicked header had given Real the lead in the 24th against a determined Las Palmas, who had won their previous three league games to move clear of the relegation zone.
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Ramos was sent off in added time for a second booking, earning the 20th red card of his Real Madrid career.
The Spain international, who holds the unwanted title of the player with the most red cards in Real Madrid’s history, is suspended from next Sunday's match against former side Sevilla as is Portuguese centre-back Pepe.
Third-placed Real are 10 points clear of fourth placed Villarreal, who lost 4-2 at fifth placed Sevilla.
Madrid coach Zinedine Zidane did not hide his feelings about his side’s display after the match.
"I’m very worried about our second half performance. We gave the ball away an incredible amount of times and if we want to achieve anything this season we have to play better, that’s clear," he told a news conference.
"We won’t get anywhere playing like this."
A stunning long range goal from Ukraine international Yevhen Konoplyanka kept up Sevilla's hopes of taking Spain's fourth Champions League spot from Villarreal.
Konoplyanka's 30-yard strike restored Sevilla's lead on 65 minutes after Cedric Bakambu's double had given Villarreal a 2-1 lead before half-time and a Victor Ruiz own goal in the 51st minute that made it 2-2.
Substitute Jose Antonio Reyes finished off a quick counter attack for Sevilla's fourth goal in injury time, despite the hosts playing the last 10 minutes with 10 men after Ever Banega was sent off for a second yellow card.
Konoplyanka’s afternoon also turned sour as he was forced off with a suspected muscle injury and could miss the second leg of Sevilla’s Europa League Round of 16 tie with Basle on Thursday after a goalless first leg.
Athletic Bilbao joined the fight for a top-four finish by beating Real Betis 3-1 thanks to a double from Sabin Merino, and sit six points behind Villarreal, in sixth place.
Merino's goals came either side of Mikel Rico's strike, while Ruben Castro got a consolation for the visitors.
(Reporting by Richard Martin, editing by Alan Baldwin)
