Okazaki, who scored two goals for Japan in the FIFA Confederations Cup, moves to Thomas Tuchel's side on a three-year-contract.

The 27-year-old joined Stuttgart joined from Shimizu S-Pulse in 2010.

Okazaki has been prolific for Japan in recent times, scoring 35 goals in 66 appearances, however he has failed to replicate that form for Stuttgart despite becoming a first-team regular at the Mercedes-Benz Arena.

Tuchel, however, believes Okazaki will be an important player for the Coface Arena outfit.

"We are very pleased that Shinji Okazaki has decided to switch to us," Tuchel told the club's official website.

"He is a player with skills that are very important to play our type of football. He is a complete team player, flexible, is always a goal threat and is strong going forward."

Okazaki made 42 appearances for Stuttgart last term, scoring four goals.

He will now remain with Mainz, who finished 13th in the Bundesliga last season, until June 2016.