Former Brazil international Willian has rejoined Fulham until the end of the season, the Premier League club said on Thursday.
The former Arsenal and Chelsea player, who left Fulham in August after two years at the club, moved to Greek side Olympiacos in September before becoming a free agent in January.
"I'm really happy to be back here," Willian, 36, told the club website. "I'm fully motivated to get on the pitch and do things well for this club."
Willian, who plays as a left winger or attacking midfielder, made 58 Premier League appearances in his first spell at Fulham, scoring nine goals.
This latest move is subject to international clearance.
"I'm completely happy, my family's happy," Willian added. "It's a great opportunity."
Fulham are in ninth place in the Premier League.
Manager Marco Silva recently lost winger Harry Wilson to a long-term injury.
