Atletico Madrid have hired Abel Resino as coach to replace Javier Aguirre, who stepped down after agreeing to end his contract, the Primera Liga club's president Enrique Cerezo said on Tuesday.
Cerezo said in an interview with Cadena Ser radio that the club had reached an agreement with former Atletico goalkeeper Resino, who is coach of second division Castellon.
"We have chosen Abel because we believe he is the right solution for the current situation," Cerezo said.
Atletico have not won a match this year and slipped to seventh in the standings after a 2-1 home defeat by Real Valladolid on Sunday.
The 49-year-old Resino also had brief spells as coach of Levante and Ciudad de Murcia, and takes charge just over three weeks before the first leg of the club's Champions League last 16 tie against Porto.
Earlier on Tuesday, Aguirre said he had stepped down after agreeing with Cerezo to end his two-and-a-half year term as coach.
"We have reached a good agreement," the Mexican told Cadena Ser. "I am the first to understand that I am a fundamental part of the problem the team finds itself in.
"We are adults, it doesn't matter. It's the easiest for everyone and the least traumatic."
Aguirre joined the Madrid side from Osasuna in 2006 and became the first coach since they returned to the top flight in 2002 to last more than one campaign.
The former Mexico coach steered the club into the Champions League with a fourth-placed finish last term, their first appearance in the competition since the 1996-7 season.