Osasuna have decided not to report Real Madrid for the alleged improper use of 18-year-old Franco Mastantuono in their La Liga match, according to COPE. However, the controversy surrounding the player’s registration is far from over, as other clubs could still take action in upcoming fixtures.

Under league rules, any club has 24 hours after a match to file a complaint regarding an improper lineup. Osasuna had until 14:00 local time to lodge a protest but chose not to pursue the issue.

The situation stems from Mastantuono being registered with Real Madrid’s reserve team while making appearances for the first team. Although he was officially presented as a senior signing, he wore the No. 30 shirt — typically assigned to Castilla players — when he came on in the second half against Osasuna.

Miguel Galan, president of the National Centre for Football Coaches (CENAFE), argued that Madrid breached the regulations through “improper alignment” and showed “bad faith” in registering the player with the reserves to bypass the first-team squad number rules.

Despite Osasuna stepping aside, Galan warned that the threat remains: any club Madrid face in La Liga could still file a complaint if Mastantuono plays again under the same circumstances. Real Oviedo — Madrid’s next opponent — could potentially contest the match if they choose to act within the legal window.

For now, Madrid avoid sanctions, but the club remains under scrutiny. Unless the registration issue is clarified or Mastantuono is officially registered with the first team, future rivals may be tempted to file a formal protest — putting pressure on Madrid to resolve the situation quickly.

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