According to Knights club legend Matthew Johns, Sims has told teammates he is leaving immediately after not agreeing to exercise an option for 2017 on his current deal with club.

"He told the players after the training session that the Knights game against Parramatta will be his last for Newcastle," Johns told the Triple M Grill Team.

Although Manly are also in the running for Sims signature, Johns said he has heard Sims will be going to St George Illawarra.

"My mail is he's going to be at the Dragons," he said.

The Knights co-captain made the journey south from North Queensland in 2015 but it is believed the security of a long-term deal is behind his move. AAP