Marin relishing chance to shine at Fiorentina
After coming through Borussia Monchengladbach's ranks and moving to Werder Bremen in 2009, the winger's form was enough to convince Chelsea to part with an estimated £10 million to secure his services in April 2012.
Injury prevented Marin from hitting the ground running at Stamford Bridge with subsequent struggles for game-time under Roberto Di Matteo and Rafael Benitez in 2012-13.
The 16-cap Germany international spent last season on loan at Sevilla, chipping in with seven assists in 30 appearances, and hopes to have a similar impact at Fiorentina.
"I'm looking forward to an exciting time at ACF Fiorentina and I will do my best to support the team," he wrote on Facebook. "I will learn Italian as fast as possible but for the time being I will still need the help of an interpreter.
"My special thanks go to Sevilla FC and to all the fans.
"It was a great experience to play in Spain and I had an amazing time with lots of fun."
Fiorentina get their Serie A campaign underway at Roma on Saturday, when Marin could come up against former Chelsea team-mate Ashley Cole.