OFFICIAL: Monaco sign Troyes youngster
France Under-21 international Grandsir will join Leonardo Jardim's men officially on July 1, with the fee understood to be €3million.
In 36 Ligue 1 appearances last season, the 21-year-old scored three goals and supplied four assists for Troyes, whose relegation was confirmed by a 3-0 defeat against Monaco on the final day of the season.
"I am very happy to join Monaco, an ambitious club that trusts young players and allows them to develop their full potential," Grandsir said.
"I will work hard to demonstrate my qualities and give the club the confidence it grants me."