Barcelona have signed Valencia defender Jeremy Mathieu on a four-year deal for a fee of £15.8m.
Mathieu, 30, has won two caps for France and can play at left-back or centre-back.
He will replace former captain Carles Puyol, who has retired from playing after 15 years at the club.
A Barcelona statement said: "The cost of the transfer of Mathieu is 20m euros and the buyout clause will be 50m euros."
Mathieu made 126 league appearances in five seasons at Valencia, scoring six times.
Barcelona - who finished second in La Liga last season - have had a busy summer under new coach Luis Enrique.