The 30-year-old hooker, widely regarded as one of the world's best in his position, has been a key figure for the Spears since joining the club in 2021. The extension follows a disappointing end to their 2024 campaign, with the Frans Ludeke-coached side falling to Toshiba Brave Lupus in Sunday's League One final.
Marx initially arrived in Japan in 2020, signing with the Spears after a stint at NTT Shining Arcs and a standout five-year run with the Lions in Super Rugby. He has since become one of the most dominant forwards in the Japanese domestic scene, earning praise for his physicality, breakdown dominance, and set-piece consistency.
A two-time Rugby World Cup winner with South Africa, Marx was a central figure in the famed "Bomb Squad" during the 2019 tournament. He reclaimed the Springbok number two jersey during the 2023 campaign, only for a knee injury suffered against Scotland in the pool stages to rule him out of the rest of the World Cup.
Despite the setback, Marx's value to both club and country remains unquestioned. His versatility as a ball-stealing threat at the breakdown and power runner in open play has made him one of the most feared hookers in the modern game. With 21 tries in 76 Test appearances, he holds the record for most tries scored by a forward in Springbok history.
Marx's new deal underscores the continued draw of Japan's top-flight league for international talent, while also giving the Spears a cornerstone around which to build over the next three seasons.