The attacking midfielder’s £33.4m transfer from Ajax was agreed shortly after the January window had closed and his contract at Stamford Bridge comes into effect from July 1.
Until then, the Morocco international will be cheering on his new teammates from home – just like he did when the Blues returned to Premier League action last weekend and once again on Sunday afternoon.
Chelsea travelled to the King Power Stadium for an all-Premier League FA Cup quarter-final tie against Leicester City and emerged victorious thanks to Ross Barkley’s second-half goal.
The result has set up a semi-final tie against Manchester United at Wembley next month.
Such was the importance of the victory that striker Tammy Abraham – who had a goal ruled out for offside – took to Instagram to share a message with supporters.
His post was seen by Ziyech who reacted by replying with a clapping emoji, giving Abraham and co his seal of approval.