The 30-year-old Olympique de Marseille centre-back had been on the verge of returning to San Sebastián, where he spent the 2024-25 season on loan from West Ham, before the transfer unravelled at the last moment.
Speculation had pointed to a failed medical examination as the reason, but Aguerd used his social media channels to reject that version of events.
"In a conversation with the director, I'll have the chance to talk about my reintegration protocol. My medical examination went perfectly and was validated by both clubs.
"Allow me to recover fully in the best conditions, but the director can contact you immediately, with all due respect to your position.
"Regards," he wrote.
Aguerd made 36 appearances for Real Sociedad during his loan spell before returning to West Ham and then completing a permanent switch to Marseille for a fee of around €23 million in September 2025.
The Morocco international, a regular for the Atlas Lions, previously played for Rennes and Dijon in France before his move to West Ham in 2022. His statement points instead to a disagreement over the pace of his return from injury as the real reason the deal broke down, with the player understood to have favoured a gradual reintegration rather than being made available immediately, in contrast to what the Real Sociedad coaching staff wanted.
The saga has moved quickly. Reports in France on Thursday had suggested an agreement between the two clubs was all but complete, only for the deal to collapse within hours after Aguerd held a key conversation with his prospective coach. Real Sociedad had viewed the Moroccan as their priority defensive target, given his previous familiarity with the squad and the Basque country.
According to fichajes.com, the collapse leaves Real Sociedad still searching for defensive reinforcements before the transfer window closes, with the club having believed an agreement with Marseille was close to being finalised.