Nottingham Forest have completed the signing of Daniel Pinillos after a successful trial.
Doncaster have made forward Dany N'Guessan their sixth summer signing.
With right-back Franck Beria injured, Les Dogues have acted quickly to land the 23-year-old, who was contracted with Sochaux until June next year.
However, with Les Lionceaux struggling just one place off the foot of the table, they have decided to cash in on one of their assets.
The France Under-21 international, who made 85 appearances for Sochaux following his move from Le Mans in 2011, had been linked to several of Europe's top clubs, including Juventus and Arsenal.