Posted by Joao Felix has completed a six-month loan from Atletico Madrid and will don the number 11 shirt for Chelsea.
The same jersey number was worn by the Portugal international for the La Liga team.
Felix, who had a falling out with Atletico boss Diego Simeone, will get a £9 million loan fee from the Blues.
The loan agreement does not include a buyout clause, and Felix has also agreed to a one-year extension with Madrid.
This indicates that after his tenure at Stamford Bridge expires, he will probably return to Spain.
From his 14 La Liga games, the forward has four goals and three assists.