He's never played an AFL game but rugby league legend Billy Slater believes he has plenty to offer the rival code after joining St Kilda in a leadership development role.

The under-performing Saints pounced on Slater as soon as he announced his retirement from the Melbourne Storm and he will begin working two days a week during the pre-season.

Slater isn't cutting ties with rugby league altogether, still working with the Storm in a specialist coaching role.

READ: Billy Slater is with St Kilda

The 35-year-old says he will look to impart his knowledge to St Kilda about standards, professionalism and match preparation to create a winning culture similar to that at the hugely successful Storm.

"I don't understand AFL and I don't come here as a specialist AFL coach," Slater said on Thursday.

"I think there's a correlation between the two codes and we can certainly draw some parallels.

"The specifics of the skills of the game are different but at the end of the day we're a team trying to strive for one goal - it's about a group of guys trying to work hard and be selfless and I don't think that changes just because it's a different code."

Slater felt the leadership qualities he learnt in 16 seasons in the NRL were transferable to AFL, proven in reverse with former Collingwood premiership captain Nick Maxwell's work with the Storm.

"Maxy was great at the Storm, creating an environment to get the best out of ourselves and helping develop leaders into better leaders," the 35-year-old said.

"And with first and second-year players, just building that consistency around their game and the results were shown in 2018."

WATCH: Slater on new role

He said the first part of his role would be to get to know the St Kilda players during the pre-season to find out what made the success-starved club tick – the club's single premiership dating back to 1966.

Saints football manager Simon Lethlean said Slater's signature was a major off-season coup.

"Billy's been an impressive leader in his own right, but he's also been a key member of a culture that is highly respected across all sports," Lethlean said.

"Over the course of the season, we identified that there was an opportunity to strengthen our leadership and development programs, and we think Billy can play an important role in that."