Fiorentina have complained to world governing body Fifa over Chelsea winger Mohamed Salah's loan move to Roma.
The Egypt international returned to Italy on a season-long loan in August having ended last campaign at Fiorentina on loan.
Salah, 23, scored nine times in 26 games for Fiorentina, who said they had the option to extend the loan spell and allege a breach of contract.
"The matter is still pending and being investigated," a Fifa spokesman said.
Chelsea boss Jose Mourinho said at his Friday news conference: "I'm happy that Fifa has time for other things in the middle of such grey weather around them."
Blues technical director Michael Emenalo has already defended the club's loan policy after 33 players left the reigning Premier League champions on a temporary basis this summer.
"Sometimes we know there are players whose development is not finished, just like Victor [Moses], who we want to keep with our squad but who maybe needs to play more football to get to the level we think he can get to," Emenalo told the club's in-house TV station.
"These players go to top clubs and when they get there they prove we don't recruit bad players, just like Salah did last season."
Salah joined Chelsea from Swiss side Basel for £11m in January 2014, making 13 Premier League appearances and scoring two goals.
He has played twice for Roma so far.