Ajax defender Jorrel Hato has reportedly been given permission to travel for a medical after Chelsea reached an agreement over a €40m (£34.5m).
Chelsea have been in talks with Ajax in recent days over a deal to bring the Netherlands international to Stamford Bridge.
A recent report claimed that the Blues had made a breakthrough in transfer negotiations with the Dutch giants.
According to journalist Fabrizio Romano, Chelsea have now reached an agreement over a deal worth more than €40m (£34.5m).
Hato given permission for Chelsea medical
In a separate update, Romano claimed that Hato has been 'authorised' to travel to London to undergo a medical with the Club World Cup winners.
As long as there are no surprise twists, Hato will put pen to paper on a long-term contract that will run until the summer of 2032, with an option for a further year.
The Dutchman will become Chelsea's latest signing of a busy transfer window, which has included the arrivals of Liam Delap, Jamie Gittens, Joao Pedro, Dario Essugo and Estevao.
Hato is set to depart Ajax after making 111 competitive appearances following his emergence from the club's famed youth system.
Hato set to bolster Enzo Maresca's defence
Chelsea are signing a highly-rated defender who can offer versatility to head coach Enzo Maresca.
Hato is comfortably playing on the left side of defence, meaning that he can provide cover to first-choice left-back Marc Cucurella.
The youngster is also able to play in the middle of the backline, putting him in direct competition with Levi Colwill, Benoit Badiashile, Wesley Fofana, Benoit Badiashile and Mamadou Sarr.
Hato's arrival could push Tosin Adarabioyo and Trevoh Chalobah down the pecking order amid uncertainty surrounding their respective Stamford Bridge futures.
Axel Disasi and Renato Veiga are already expected to leave before the transfer window shuts later this summer.