Lyon completed the signing of midfielder Pape Cheikh Diop from Celta Vigo on a five-year deal.
The Ligue 1 club's president Jean-Michel Aulas had confirmed that a deal was agreed between the two sides and Diop underwent a medical a day later.
The Senegal-born 20 year-old has completed his move to France for a reported initial $A15 million.
Diop, who has represented Spain at youth international level, featured 16 times for Celta in LaLiga last season, scoring once.
He becomes Lyon's seventh signing of the transfer window, after Bertrand Traore, Mariano, Ferland Mendy, Marcal, Kenny Tete and Marcelo to the club.