The Belgian centre-back has completed a move to the German club after his spell at Elland Road came to an end, with the transfer now officially confirmed by the Yorkshire outfit.
Hamburg SV have secured the services of the 27-year-old on a temporary basis for the duration of the campaign, with the loaned player retaining the option to go back to his parent club the following year. The defender made the switch to West Yorkshire twelve months ago in a deal worth approximately £5million, yet he found first-team opportunities hard to come by during the most recent season, earning just five starts in the top flight alongside twelve appearances from the bench.
Many of those run-outs came as cover for injured colleagues at the back, and speculation about a potential exit had been circulating since the end of the previous season.
Sources indicate the German side hold a purchase option but are not compelled to sign him permanently, meaning he is currently scheduled to report back to Leeds when the campaign concludes.
Nevertheless, the player seems to have acknowledged his chapter at the club is over, conveying as much in a message posted on social media on Tuesday evening. He addressed Leeds supporters warmly, describing his time at the club as a short but memorable chapter. He expressed gratitude for feeling welcomed from his first day, mentioned his love for the club badge and the atmosphere at Elland Road, and wished everyone well.
The club released their own announcement on Wednesday morning to formalise the switch. Their statement confirmed that Sebastiaan Bornauw had joined German Bundesliga side Hamburg SV on loan for the remainder of the 2026/27 season. The 27-year-old defender signed for the Whites in the summer of 2025 upon their return to the Premier League, arriving from VfL Wolfsburg. Bornauw made his Premier League debut for the club in December 2025 as a late substitute in the 3-1 win over Chelsea at Elland Road, and from there was a regular in matchday squads under Daniel Farke, making 17 appearances across all competitions. He now joins a Hamburg side which finished 13th in the German top-flight last season under Merlin Polzin, and their league campaign this year will begin with a trip away from home to Borussia Dortmund. Everyone at Leeds United would like to wish Seb the best of luck during his time away from the club.