Atletico Madrid was so poor in the first half against fourth-division visitor Sant Andreu that a shock Copa del Rey elimination wasn't a far-fetched possibility on Wednesday.

But with three goals in the opening 10 minutes of the second period, Atletico's second-string team put an end to any fears of an upset at Wanda Metropolitano Stadium.

Thomas Lemar scored in the 48th minute, Nikola Kalinic in the 53rd, Angel Correa in the 55th and Victor 'Vitolo' Machin in the 81st to secure a 4-0 win and a place in the last 16 following a 5-0 aggregate victory.

Atletico was without Diego Costa, Antoine Griezmann and several other regular starters rested by coach Diego Simeone, who was banned from the bench as he served the second of a three-game suspension following a rant in a Copa match against Sevilla last season.

The home side struggled in the first half, with goalkeeper Antonio Adan forced to make several saves.

Substitute Lemar went on at halftime and was key for Atletico, opening the scoring with a right-footed shot from outside the area. Kalinic added a header and Correa produced a fine finish with the outside of his right foot. Vitolo's goal from close range came after a pass by Saul Niguez.