Calero arrives at La Rosaleda as a free agent after leaving Espanyol, and has signed a contract with Malaga running until June 2027, with the option of a further year should certain objectives written into the deal be met.
The club say the move to bring in the centre-back reflects head coach Juan Francisco Funes' plan not to sign another player in that position, instead trusting in the recovery of Alex Pastor to provide further cover and competition alongside Calero.
Pastor has completed his first two pre-season sessions at the same level as his team-mates, leaving behind the serious knee injury that ended his campaign prematurely last season.
The Catalan defender has recovered from the ligament damage in his right knee and the subsequent meniscus surgery that followed during his rehabilitation, with the start of pre-season set to prove decisive for his prospects this year.
Malaga underlined their faith in Pastor last season by extending his contract to 2028, a move that did not go unnoticed given he was in the midst of a long-term recovery at the time. With Calero now arriving as a new partner in central defence, Pastor will be aiming to recapture the form that had made him a key figure before his injury.
The setback occurred early in the 2025-26 season, when a training session left Pastor with a complete rupture of the anterior cruciate ligament, damage to the inner meniscus and a mild injury to the medial collateral ligament in his right knee, a diagnosis that ended his campaign there and then. His recovery was not without further complications, as he required a second operation to resolve a meniscus issue, delaying his expected return. Because he did not occupy a squad registration slot, Malaga were able to manage his recovery without added pressure, and Pastor is now working entirely normally alongside the rest of the group as he looks to rediscover his pre-injury level.
Calero's arrival also marks a personal homecoming. The defender came through Malaga's academy between 2013 and 2016, representing the club at Juvenil and Atletico Malagueno level, before returning to Real Valladolid, from where he made the step up to professional football ahead of a seven-season spell at Espanyol. A decade after leaving the club, he will finally have the chance to make his debut for Malaga's first team.