Danish international Mohamed Daramy has joined Reims from Ajax after the French side paid a club "record sum", team president Jean-Pierre Caillot said
Daramy, 21, the youngest scorer in the history of former club FC Copenhagen aged 16, has signed a five-year deal. Financial details were not revealed.
"With this major signing, we're closing the transfer window for new signings," said club general manager Mathieu Lacour.
Reims start the season with high hopes after spending over 10 million euros on Kenyan international Joseph Okumu and a similar sum for Japanese international Keito Nakamura.
Eleventh last season in Ligue 1, Reims open their season on Saturday at Marseille.