Koscielny's World Cup hopes at risk after being carried off injured
The France international went down off the ball in the eighth minute and immediately appeared to be in agony, holding his heel and beating the turf with his fist.
It was quickly decided to withdraw him and he was helped on to a stretcher before being carried off and replaced by Calum Chambers, with Atletico players – including international team-mate Antoine Griezmann – among the concerned onlookers.
Koscielny would have expected to be in the World Cup squad for France, whose campaign begins against Australia on June 16.
Our skipper leaves the field on a stretcher
@6_LKOSCIELNY@CalumChambers95#ATLvAFC 0-0 (12)
1-1 on aggregate pic.twitter.com/a1tH8LAGBs
— Arsenal FC (@Arsenal) May 3, 2018