"Renato had to have a scan before he travelled and the doctor in Munich decided it was better to stay one more week," Carvalhal told a news conference ahead of Saturday's league clash against Everton.
"The information I have is that he will have another scan on Monday or Tuesday and if everything is okay, he will travel. He wants to come... I believe he can be involved before the end of the season," the manager added.
Midfielder Sam Clucas faces a late fitness test to be ready for the home clash after picking up a knock on Wednesday while centre back Mike van der Hoorn could be ready for action after suffering a shoulder injury last weekend.
Swansea are 15th in the table with 32 points from as many games while Everton are ninth with 41 points.
(Reporting by Shrivathsa Sridhar in Bengaluru; Editnig by Toby Davis)
