The Eredivisie side will reportedly also have the option to make the deal a permanent one next summer. De Telegraaf add that Castillo was at the Ajax’s Sportpark De Toekomst on Thursday to complete his medical and paperwork.
The highly-rated left-back was signed by Chelsea from Ajax in 2016 and has been a part of their academy team for the last 3 years. The teenager is versatile and has played for the Blues in the midfield and as a winger too.
He was set to leave in the summer after his contract expired at the end of the last season. However, the arrival of Frank Lampard changed things and he performed a U-turn to sign a new deal at the club.
Castillo’s new deal runs out in 2022 and with Lampard preferring Emerson and Marcos Alonso in the first team, the Dutch star has decided to leave on loan.
Reports suggest that Chelsea will be making a move for Ben Chilwell next summer and that would shut the door for Castillo to make it into the first team. At Ajax, he will play as a backup to Nicolás Tagliafico, someone who has been linked with a move away as well.