"It's going to be an important game for the club," Atletico coach Diego Simeone said. "We've reached the last round three points above Barcelona — nobody would have believed we had a chance to win, but here we are, alive still."
Barcelona, which counted itself out of the title race only eight days ago, came out at Elche with intention but eventually seemed to settle for its result when word of Malaga's first goal arrived.
Andres Iniesta volleyed a shot off the crossbar early on before goalkeeper Manu Herrera got a touch to Lionel Messi's effort in the 38th to tip it around the far post. Herrera denied Messi again after the restart, but the defending champions barely threatened again.
"It's going to be a great week ahead and for some of us it could be our last game with Barca so it would be a nice way to go out," Barcelona defender Javier Mascherano said.
Atletico hasn't lost to Barcelona this season, drawing in four matches before finally beating the Catalans in the second leg of the Champions League quarterfinals.
Two teams will join Real Betis in being relegated to the second division on the last day after Almeria and Getafe secured victories to improve their chances of staying up. Real Valladolid allowed Betis to rally back three times before eventually losing 4-3 to the last-place club.
Almeria, which won 2-0 at Granada, and Getafe — a 1-0 winner over Sevilla — share 39 points.
Granada has 38 points ahead of its finale at Valladolid, which is tied on 36 points with Osasuna in the final two drop places. Osasuna drew 1-1 at Espanyol.
Athletic Bilbao and Real Sociedad drew 1-1 in a Basque derby.
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