Atletico Madrid gave renewed hope to their La Liga title rivals on Saturday by losing 2-0 at home to Levante and missing the chance to extend their six-point lead at the top of the table.
The defeat is only Atletico's second in the league this season and their first at the Wanda Metropolitano in any competition since Barcelona beat them there in December 2019.
It means what could have been a commanding 11-point advantage at the top of the table is now just six, with Real Madrid, the closest challengers, up against Real Valladolid later on Saturday.
Due to rearranged fixtures, Atletico were facing Levante for the second time in four days, having already dropped two points against them in an away 1-1 draw on Wednesday.
And Levante proved that was no fluke by going one better, their impressive victory inflicting another setback on Diego Simeone's side, who will have to rediscover their rhythm for Tuesday's Champions League last 16 first leg at home to Chelsea.
Luis Suarez will be up against English opposition again in midweek and the Uruguayan went closest to finding an equaliser, his bending free-kick in the second half coming back off the post.
Suarez has now gone three league games without scoring for the first time this season.
Jose Luis Morales had already put Levante in front after half an hour and while Atletico huffed and puffed for most of the second half, they could not find a way through.
With goalkeeper Jan Oblak up for a corner in injury-time, Jorge de Frutos made it two by launching into an open net.
Atletico have now gone seven league games without a clean sheet, their longest run since Simeone became coach in 2011.
Another concern for Simeone will the fitness of central defender Jose Gimenez, who had to go off injured in the second half, making him a doubt to face Chelsea in midweek.
They were given an early warning by Levante when one long pass from Ruben Rochina was all it took to send Morales in on goal but despite a superb first touch, the striker dribbled his finish wide.
But Morales found the net after half an hour, this time with a bit of luck to help him. Geoffrey Kongodbia dangled a weak leg into a challenge on the edge of the area and the ball fell to Morales to finish after a deflection from Felipe.
Gimenez waved to the bench to come off but for 20 minutes, Atletico launched an assault on Levante's goal.
Suarez's curling free-kick hit the post while Joao Felix twice failed to convert from crosses fizzed in from the right.
Correa thought he had an equaliser, poking in after a scramble in the box, but the goal was ruled out for a dubious foul by Suarez as he challenged for a ball in the air.
The chances dried up and Atletico grew desperate. Oblak ventured up for a last-gasp corner but the ball was headed away and De Frutos capitalised to confirm victory.
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