Chelsea reach agreement with Ajax for Ziyech: the official announcement
While Chelsea weren't active during the January window, they completed a deal for a significant reinforcement for next season. In fact today the Blues announced they are set to welcome Halim Ziyech to London:
Chelsea Football Club has reached an agreement with Ajax to sign Hakim Ziyech this summer. The move is subject to the player agreeing personal terms and he will remain at the Dutch club for the rest of this season.
A Moroccan international, Ziyech is a left-footed attacker who is comfortable playing off the right flank and coming inside, as he has often done in recent years to such devastating effect for Ajax, or on the left to attack with width and deliver into the box.