Nice at 80/1 odds to win Ligue 1
The 20-year-old has spent each of the past two seasons on loan at Bundesliga side Hannover and Bastia, respectively, but now joins Nice on a permanent basic.
The terms of the transfer were not disclosed by either club.
Earlier on Monday, Nice completed the signing of experienced Netherlands playmaker Wesley Sneijder on a free transfer.
Lucien Favre’s side began their Ligue 1 campaign with a 1-0 defeat to Saint-Etienne and face Napoli in the first leg of a keenly anticipated Champions League play-off clash next week.