Johannesburg - The Sharks have confirmed that several of their senior players have extended their contracts at the Durban-based outfit.
Speculation has been rife in recent months over the futures of Du Plessis brothers Bismarck and Jannie, but the union said that the two have signed new deals along with several others.
Commercial Manager, Rudolf Straeuli said: "Youngsters like Lwazi Mvovo, S’Bura (Sibusiso) Sithole, Lubabalo Mthembu and Patrick Lambie have all extended their contracts, as well as senior players like Bismarck and Jannie du Plessis and Beast Mtawarira.
"We have secured all the good young players and Springboks, none of them are leaving.
"We also have a stable coaching staff and environment and in the near future, we may be able to announce more signings."
No details of the contracts have been given, but Straeuli confirmed that several of the players have signed for at least another two seasons.This comes after news broke earlier on Tuesday that they re-signed 27-year-old lock Steven Sykes on a 12-month deal.
Sykes will boost a relatively inexperienced second row that includes Alistair Hargreaves, Ross Skeate, Anton Bresler and Jandre Marais.
"Steven Sykes is coming back," Sharks coach John Plumtree said. " As soon as I heard that he wanted to come back home, I was really interested.
"A player of his calibre is vital because of the experience he offers us, especially in this (Super Rugby) competition."
Sykes only made his Leinster debut four months ago after leaving the Durban franchise at the end of the Super Rugby season.
Plumtree added: "We have some really nice young locks coming through, but Super Rugby is a really tough competition, a long one, and having his experience in the second row is going to be really valuable.
"It also adds a little more competition for places. "He has that physical nature to his game and some of our younger locks are physical as well, but he gives us that experience that we need."
The Sharks, who face the Bulls in their opening match of the Super Rugby season on February 24, have an internal trials match next weekend.
They then play Currie Cup First Division champions Boland on February 10 at Kings Park, followed by an away friendly at the Eastern Province Kings.