Chelsea defender Ian Maatsen is heading away from the club on loan this winter.

The left-back has agreed to join Borussia Dortmund for the rest of the campaign.

Per The Sun, his deal has not yet been ratified, as Chelsea have the maximum number of players out on loan.

According to the source, Chelsea must first rip up a current deal to allow Maatsen to depart.

One of the options would be to recall Hakim Ziyech from Galatasaray and then sell him permanently.

Ziyech has not been impressive during his spell at Gala, which would complicate that scenario.