Brest announced on Saturday that Julien Lachuer would take over as head coach following the death of Eric Roy.
Roy died earlier this month, aged 58, after suffering from pancreatic cancer.
Frenchman Roy, who was diagnosed in 2023, guided the Breton club to a 12th-placed finish in the French Ligue 1 last season.
It was his wish that assistant Lachuer, 49, took over.
Lachuer is a long-time Brest employee, having first touched down as a goalkeeper in 2005 after a career with French clubs Valenciennes, Angers and Amiens.
He joined the coaching staff after his retirement from playing in 2010 as a goalkeeper coach before being named assistant in 2022.