Bolton coached Carlton from 2016 to 2019 in between separate stints at Hawthorn.
The 45-year-old spent the past three years as Collingwood's director of coaching, playing an important off-field role in the club's run to the flag in 2023.
But it hasn't been smooth sailing for the Magpies on or off the field this year.
Collingwood football boss Graham Wright took a sabbatical earlier this year amidst rumblings of tension between him and Magpies chief executive Craig Kelly.
Wright decided not to return to the Magpies, and has since signed with Carlton to become the Blues' next chief executive in a handover with current CEO Brian Cook.
Bolton helped fill the void left by Graham's absence at Collingwood this year, and it's been reported there was friction between himself and Magpies list manager Justin Leppitsch.
The Saints announced on Tuesday that both Bolton and former Melbourne and Geelong defender Jared Rivers had signed up as assistants for 2025.
Bolstering our coaching panel 💪— St Kilda FC (@stkildafc) We are pleased to welcome Brendon Bolton and Jared Rivers to the club.Details 🗞�👇October 15, 2024
Rivers spent four seasons at Collegians Football Club in the VAFA A Grade competition, leading the club to the 2023 premiership in his final year at the helm.
The Magpies are still on the lookout for a permanent football manager.
"While I am incredibly grateful for my time at Collingwood, my passion right now remains on playing a role as a coach in an AFL program which I am looking forward to getting stuck into," Bolton said in a statement.
In other coaching movements, Fremantle have signed Jade Rawlings as their new backline coach on a three-year deal following the departure of Matthew Boyd.Â
Rawlings joins Justin Longmuir's coaching panel alongside Jaymie Graham (forwards), Joel Corey (midfield) and Harry Garland (stoppages).Â
View this post on Instagram A post shared by Fremantle Dockers (@freodockers)
The 47-year-old has spent the past four seasons as senior coach of Norwood in the SANFL, guiding the club to the 2022 premiership and the 2024 grand final.Â
Rawlings has been part of coaching panels at Brisbane, Richmond, Melbourne and North Melbourne following a 148-game AFL career across stints with Hawthorn, Western Bulldogs and North Melbourne.
West Coast have signed Jamie Maddocks as the club's new head of development.
Maddocks has been the Western Bulldogs' head of development for the past five seasons, after joining the club as a development coach and opposition analyst in 2015.
He joins a revamped West Coast coaching group under new head coach Andrew McQualter.
Just last week, West Coast announced club great John Worsfold had returned to the club in the role of head of football.
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