On the eve of the one-year anniversary of the "blackest day in Australian sport", Cronulla have been rocked by news a third player is now suing the club.

Fairfax Media can reveal that former player Broderick Wright is taking legal action against the club, joining ex-teammates Isaac Gordon and Josh Cordoba in a lawsuit against Cronulla.

Wright's lawyers sent the Sharks a letter of demand on Wednesday afternoon informing the club of their former player's decision to sue them for negligence, breach of contract and intentional tort during a period in 2011 when controversial sports scientist Stephen Dank ran a supplements program.

"It's been a long and difficult time since details of the supplement program were revealed," Wright said. "I have been troubled by the obvious abuse of trust by Cronulla, but what they put me through by subjecting me to the program and exposing us to unknown risks was just wrong and I feel I need to make it right. I love rugby league and seeing the other guys come forward gave me strength to speak up too.”