St Kilda have announced that former Carlton mentor Brett Ratten will join the Saints as an assistant coach.

Ratten is currently serving as an assistant under four-time premiership coach Alastair Clarkson at Hawthorn, and will begin his role at the Saints at the conclusion of the Hawks' 2018 campaign.

“Brett is one of the most experienced assistant coaches in the game and we look forward to the impact he can have on our football program,” Saints general manager football Simon Lethlean told the club website.

“He is highly regarded across the football industry and as midfield coach at the Hawks, was a key driver in their premiership success.”

Ratten joins former Port Adelaide and Richmond coach Brendan Lade as new inclusions to St Kilda's coaching team.

Ratten was a senior coach at Carlton from 2007-12 before spending the past six seasons at Hawthorn.

“We respect that Brett’s focus is rightfully still on his current role at Hawthorn, however, we look forward to welcoming him and his family to the Saints over the off-season,” Lethlean added.