Marcos Alonso is heading to London with the Fiorentina defender set to complete his move to Chelsea, according to Sky sources.
It is understood that both clubs have agreed a fee for Alonso. Personal terms have also been agreed with the player.
SSNHQ reported earlier on Tuesday that the Italian side would be happy with a fee of £24m.
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It is understood the Blues had an initial £20m offer rejected by the Serie A club for the left-back, with Fiorentina holding out for £27m.
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However, Alonso is keen to finalise a move back to English football and a formal announcement on a deal to take him to Chelsea seems to be a formality.
The 25-year-old is set for his third spell in the Premier League, having played for Bolton between 2010 and 2013 and spending a six-month loan spell with Sunderland in 2014.
Alonso, who came through the Real Madrid academy and has represented Spain at U19 level, made 75 appearances in all competitions for Fiorentina in two seasons with the club, helping the Italian side to a fifth-placed finish in Serie A last campaign.