The German-Japanese goalkeeper began his youth career at Kawasaki Frontale before moving to Germany at the age of 14 to join Alemannia Aachen. He later switched to Werder Bremen’s academy. After making nine appearances for Werder’s reserves, Mio Backhaus spent the 2023/24 season on loan at Dutch top-flight side FC Volendam, where he was first-choice goalkeeper and played 33 Eredivisie matches. Following his return to Werder, he made his Bundesliga debut in August 2025 and has since made 32 Bundesliga appearances for the Green-Whites.

The 22-year-old has represented Germany at every youth level from U15 upwards and is currently part of the U21 side.

“Mio made a real impression in his first Bundesliga season and showed the level he is already capable of playing at. His calm, focused presence is something that can rub off on those around him,” said board member Jochen Saier. “His game covers every aspect of what we look for in a goalkeeper, he has plenty of potential to keep developing and is someone we believe will fit really well into the group. With Mio, we’ll continue to have an excellent goalkeeping trio going forward.”

Mio Backhaus added: “An opportunity came up that felt like the perfect fit for me. The overall package – the people I spoke to here, the city, the stadium and the football played in Freiburg – led me to this decision. I want to achieve something with the team and I’m really looking forward to joining SC.”

Both parties have agreed not to disclose the details of the contract.