According to AZ's official channels, 22-year-old Sin will leave the club to join ADO Den Haag for the upcoming season. VoetbalPrimeur reports that Sin will have more opportunities to play in the Eredivisie with his new club. Sin was signed by AZ last year for a reported four million euros from Banik Ostrava, and has also been used as a right winger. Despite not featuring in AZ's first team this season, Sin has played matches for Jong AZ in the Keuken Kampioen Divisie.
Sin's contract with AZ will expire in 2030, and there is no option for ADO Den Haag to buy him permanently. This means that Sin will return to AZ after his loan period ends. Transfermarkt estimates Sin's market value at three million euros.