Barcelona lost Lionel Messi to injury and a chance to beat a direct title rival on Wednesday, when it was held to a 1-1 draw by Atletico Madrid in the Spanish league.
Messi gingerly walked off the Camp Nou pitch in the 58th minute, just moments before Atletico substitutes Angel Correa and Fernando Torres went on and linked up to equalize.
The night couldn't have started better for Barcelona, after seeing Real Madrid's hopes of breaking its Spanish league record for consecutive wins dashed by a 1-1 draw with Villarreal.
Ivan Rakitic put Barcelona in front with a headed goal in the 41st minute.
But the match quickly changed course when Messi came up lame following a sprint to fight for a ball with Diego Godin.
The Argentina star grimaced as he touched his right thigh. After walking gingerly for a few minutes, he sat on the turf, pulled out his shin guards and unlaced his boots.
Arda Turan hastily warmed up and rushed on to replace him.
Sensing an opportunity to transform the game, Atletico coach Diego Simeone sent on Torres and Correa.
The move immediately paid off when they caught Barcelona napping after a foul. Torres's glancing touch of a pass left Correa clear to rifle a low shot off the post and into the net in the 61st.
Neymar tried to lead Barcelona in Messi's place, while Godin drew a save from goalkeeper Marc-Andre ter Stegen in the final minutes.
League leader Real Madrid leads Sevilla by two points. Barcelona is three behind, followed by Atletico at four points back.
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