Eintracht Frankfurt have swooped for Real Sociedad defender Vadim Demidov for an undisclosed fee.
Eintracht coach Armin Veh recently said he needs three defenders to complete his summer shopping spree.
"We are very pleased to have been able to bring this transfer to a successful conclusion for Eintracht Frankfurt," said the club's director of sport Bruno Hubner in a statement.
"We have been able to sign a strong central defender who has leadership qualities and therefore fits into the team profile of Eintracht Frankfurt and head coach Armin Veh."