The Sharks have extended the services of locks Reniel Hugo and Emile van Heerden, along with fullback Anthony Volmink and prop Dian Bleuler.
Hugo (31), who can also play flank, has signed a new two-year deal with the Durbanites, along with 21-year-old Van Heerden, while Volmink (32) and Bleuler (22) have re-signed until 2024.
The Sharks recently signed Springbok centre Rohan Janse van Rensburg, as well as Lions stars Vincent Tshituka and Carlu Sadie, from next season.
Varsity Cup recruit Nevaldo Fleurs has already made his debut, while Bok enforcer and World Cup winner Eben Etzebeth is due to arrive in July.
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