German club, Borussia Dortmund has become a major blow to the defensive.
Turkish star, Omer Toprak has officially signed a contract with Dortmund.
Toprak was the backbone of the Leverkusen defense has accepted the transfer to Dortmund.
Verdhezinjtë pay 12 million euros for Leverkusen, while Toprak will join them in the summer.
27-year-old has signed a contract for the next five years with Dortmund.