Sky Sport and The Guardian journalist Fabrizio Romano and beIN Sports and CNN correspondent Tancredi Palmeri have both confirmed that Chelsea will sign midfielder Marcos Alonso.
Romano explained on Twitter that the Blues made a last offer of €27million to secure the services of the Spaniard.
Palmeri has confirmed the fee in one of his tweets.
Fiorentina rejected Chelsea's first offer for the player believed to be in the region of €27million but are expected to accept their latest offer.
It would be Alonso's third spell in the Premier League having featured for Bolton between 2010 and 2013 and having spent six months on loan at Sunderland in 2014.
He was one of the most impressive players in Paulo Sousa's Fiorentina last season and will become Antonio Conte's fourth summer signing if the transfer goes through.
