Chelsea are working to get the paperwork in place so that Enzo Fernandez, the Blues' new signing, is available to play against Fulham on Friday.
The Argentine signed for the London club on the last day of the transfer window for a record 121 million euros and could arrive in time for the Stamford Bridge side's next league game.
"We've got to get the paperwork in order and get the green light, so we'll see," Graham Potter told a press conference on Thursday.
Chelsea have previous experience of Joao Felix, who was able to play, also against Fulham, just a day after landing in the UK after completing his loan move from Atletico Madrid.
Of the Argentine midfielder, Potter said he is an "impressive young man" and is looking forward to working with him, as well as mentioning the language problem.
"My Spanish is not very good and neither is his English, but we will understand each other," said the British coach.