Kasey Bos has enjoyed a meteoric rise since bursting onto the scene last year. aleagues.com.au looks at his rapid journey from Melbourne Victory to Bundesliga side Mainz.
Just over a year ago, Kasey Bos sat down with aleagues.com.au and outlined his ambitions.
“I have goals in the back of my mind. Hopefully to play for my country in the future,” he said in May last year. “For now, playing consecutive minutes in the A-League and build my confidence. Hopefully follow in my brother’s footsteps and move across to Europe.”
Bos had just broken into the Melbourne Victory first team, making his Isuzu UTE A-League debut three months earlier.
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Fast forward to now and the 21-year-old is indeed following in his brother’s footsteps after earning a European transfer.
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“Kasey Bos is a very strong left winger who, with his defensive and offensive strengths as well as his dynamic and courageous style of play, fits the profile we are looking for very well,” said Mainz’s sporting director Niko Bungert.
“He has already proven his talent in the A-League. We believe that with his potential, he can also hold his own in the Bundesliga and continue to develop well with us alongside a seasoned professional like Phillipp Mwene.”
Less than a month ago, Kasey Bos was playing in an historic Isuzu UTE A-League Grand Final at AAMI Park. Now, he is calling the Rhine-Main Metropolitan Region home. He also recently was just called up the Subway Socceroos for the first time.
It has been a rapid rise for the Victory academy graduate, who is the first Aussie to play for Mainz since Nikita Rukavytsya between 2011-13.
Like his brother and Westerlo full-back Jordy, Kasey Bos too played for Melbourne City.
The siblings spent time time together within the club’s academy setup but City’s relocation from Bundoora to Casey – in the outer south-eastern suburbs of Melbourne – in 2021 led to a cross-town switch to their rivals.
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Bos made his A-Leagues debut against Central Coast Mariners in February 2024, while he came off the bench and helped inspire Victory’s unforgettable Elimination Final comeback against former club City last season.
Kasey Bos thrived in the navy blue of Melbourne Victory, playing a key role in Victory’s promotion from NPL3 to the second tier of Victorian football in 2023.
After 43 minutes of A-Leagues football in 2023-24, Bos came into his own this term.
The talented Australian broke out as one of the most exciting talents in the competition with four goals in 26 appearances, totalling 2,102 minutes as Arthur Diles’ Victory fell narrowly short of a Championship.
“The discussions with the sporting management were great, and the city itself also makes a really cool impression,” said Bos. “The Bundesliga is extremely exciting for me, and the level of play is top-notch.
“Mitchell Langerak, my teammate from Melbourne, has already given me some tips. I’m now looking forward to getting to know the team and the fans soon and exploring Mainz further.”
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