Atletico Madrid overcame tough conditions on wet artificial turf to beat fourth-division club Sant Andreu 1-0 on Tuesday to open their Copa del Rey campaign.
Portugal forward Gelson Martins scored a 33rd-minute winner for the visitors, who played without Antoine Griezmann and most of their regular starters.
Atletico also didn't have coach Diego Simeone on the bench as he served the first of a three-game suspension following a rant in a Copa match against Sevilla last season.
Under heavy rain on a challenging field, Atletico controlled the game despite the absences, but their opponent put on a good fight and nearly got the equaliser in the end. The club from Barcelona had three good chances in the final minutes, including a close-range header that hit the crossbar.
"We allowed them to stay in it," Atletico goalkeeper Antonio Adan said. "The series is still open and we will have to finish it off in the match at home."
Martins scored from inside the area for his first goal since joining Atletico in the summer. He was making his sixth appearance with the club.
Sant Andreu are the only fourth-division club still left in the Copa del Rey. They also faced Atletico in the Copa five years ago, losing 4-0 at home and 2-1 in Madrid.
"We had a couple of chances to equalise," said midfielder Ton Alcover, one of the players who also faced Atletico five years ago. "We played a great match."
Simeone used most of the players the club signed in the offseason, including Martins, Adan, Santiago Arias, Rodrigo, Thomas Lemar and Nikola Kalinic.