Arsene Wenger'sArsenal face Atletico in their semi-final first-leg on April 26 (8.05pm) with the return leg a week later in the Spanish capital, on May 3.
Atletico are former winners of the Europa League with triumphs in 2010 and 2012, whioe the last time Arsenal made it to the final of the UEFA Cup was in 2000. The London side won 6-3 on aggregate.
Arsenal beat CSKA Moscow to advance to the Europa League semifinals.
"Diego Costa had to be taken off in the 52nd minute on Thursday's match against Sporting CP".
Sitting in second spot in La Liga behind Barcelona, Simeone's men are a playing below their level in the second tier European tournament.
The Europa League remains Arsenal's salvation this term as it is their only chance of winning silverware, and also because it is their only chance of qualifying for the Champions League given their poor domestic form.
However, they were knocked out of the respected group in the Champions League and have taken the competition by storm.
The Gunners saw off CSKA Moscow in the previous round.
Meanwhile, Marseille progressed after dumping RB Leipzig out of the competition, winning the tie 5-3 on aggregate.
Marseille are unbeaten at home in this season's Europa League and will have the backing a fanatical crowd when they host Salzburg in the first leg.
The Gunners' 2-2 draw against CSKA Moscow in Russian Federation on Thursday night gave them a 6-3 aggregate win to put them within touching distance of next month's final in Lyon.