The 45 year old Englishman arrives on the south coast with a wealth of experience, having started coaching at Crystal Palace in 2004.
Garner was later appointed first team coach in 2012, helping manager Ian Holloway win promotion to the Premier League via the play-offs.
The Kent-born coach helped the Eagles retain top-flight status for two years before spells with West Bromwich Albion and Indian outfit ATK.
He completed his UEFA Pro License in 2014, shadowing Jose Mourinho at Chelsea, developing a reputation for attacking, possession-based football.
Ben Garner joins Tonda Eckert’s coaching staff (Image: PA)
Garner entered senior management at Bristol Rovers in 2019, spending 11 months at the Memorial followed by a successful move to Swindon.
At the County Ground, Garner reached the League Two play-offs and guided the club to the third round of the FA Cup for the first time in a decade.
He also spent time as manager at Charlton Athletic, losing just three times in his first 15 matches, before a final short stint at Colchester United.
Garner was most recently the head coach of Right to Dream International Academy in Ghana, and he now become Eckert’s newest member of staff.
He joins assistant coaches Jeremy Newton and Ben Reeves, goalkeeper coach Ryan Flood and analyst Albert Jones, who remain in post at Saints.