Scarlets have signed South Africa number eight Uzair Cassiem from Pro14 rivals Cheetahs for the 2018-19 season.
The 28-year-old will join fellow new recruits Blade Thompson and Kieron Fonotia at the Llanelli-based team.
Scarlets head coach Wayne Pivac said: “He’s a dynamic player that likes to carry and has the ability to offload. He is a very physical individual.
“He has the ability to play across the back row but has been signed primarily as an eight.”
Scarlets are losing Scotland captain and back-rower John Barclay to Edinburgh for next season while versatile back-five forward Tadhg Beirne returns to Ireland with Munster to seek international honours.
New Zealander Thompson’s arrival from Super Rugby side Hurricanes has plugged one gap while Cassiem will fill the other.
Centre Fonotia is joining from Scarlets’ close rivals Ospreys, who have recruited Wales midfielder Scott Williams from Parc y Scarlets.