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Atleti looked destined to hold on for at most a draw after Mario Hermoso was shown a straight red card for a foul on Loren Moron, but substitute Costa steered home Yannick Carrasco's free-kick in the 74th minute to secure a top-four finish for Diego Simeone's men.

After seeing goals for Angel Correa and Alvaro Morata overturned by VAR (video assistant referee), there were concerns Costa's header would be ruled out during a lengthy check for handball.

However, the goal was allowed to stand, ensuring Atleti will return to European football's top table in 2020-2021.