Willian, having left Fulham at the end of last season, has signed with the Cottagers to the end of this season.
Fulham announced this morning: "The club is delighted to confirm the return of Willian to Fulham on a deal until the end of the season, subject to international clearance.
"Having impressed in both the 2022/23 and 2023/24 campaigns at Craven Cottage, the winger is now back in SW6 for a third spell, joining as a free agent after leaving Olympiakos at the end of December.
"He will wear the number 22 shirt."
Willian, 36, also stated: "I’m really happy to be back here. I think it’s a great opportunity again to play for this club, and I’m fully motivated to get on the pitch and do things well for this club.
“I’m completely happy, my family’s happy. We are happy to be back, and I think we can do good things until the end of the season, so I can’t wait to start with my teammates and do good things inside the pitch.”