Bayern Munich completed their first major transfer of the new season on Thursday when they signed Japan defender Hiroki Ito from rivals VfB Stuttgart.
The 25-year-old has made use of a release clause and has signed until 2028 with the Bavarians, who finished third in the Bundesliga and one place behind Stuttgart in the season just finished.
"We want hungry players who bring new energy and Hiroki has everything we want. He is a player who accepts challenges, overcomes them and continuously makes progress," Bayern's sporting director Max Eberl said in a statement.
The new defender will "immediately be a real boost for us" and new coach Vincent Kompany.
Bayern's defence struggled at times last term with Dayot Upamecano and Kim Min Jae making high-profile mistakes. There have also been reports Matthijs de Ligt might be moved on due to his high wages.
The exact transfer fee for Ito was not officially communicated but reports say Stuttgart could earn almost €30 million ($32 million), which would be a profit of €29 million.
While the money may be welcome, Stuttgart are losing a key player who helped them stun the Bundesliga to finish second and qualify for the Champions League.
They also face a fight to keep top striker Serhou Guirassy, who has indicated he would like to sign for Borussia Dortmund.