Giuseppe Rossi is set to miss Fiorentina's first game of the season at Roma on Aug. 30 after being told to rest amid concerns over his knee.
The Italy international missed the World Cup because national coach Cesare Prandelli had concerns over his fitness after he had sat out half of last season with knee ligament problems. It was the second such injury of the 27-year-old's career.
On Monday, a further examination of the knee showed that more recovery time would be needed, with a statement on the Fiorentina website saying: "The checks revealed signs of an overburdening of the right knee.
"The player will be ordered to rest and receive treatment for at least seven days, at the end of which he will undergo further checks."
That means Rossi, in addition to being likely to sit out the league opener, could also miss Antonio Conte's first game as Italy coach, in which the Italians face Netherlands in Bari.
In a recent interview with La Gazzetta dello Sport, Rossi -- who has made only 25 appearances since joining Fiorentina 18 months ago -- said he hoped he would be able to put his injury problems behind him in 2014-15.
"I'm not made of crystal, but I know that to be 100 percent, I have to do specific work and train more than the others," he said.
"But I don't want to feel restricted in any way. I've had three serious injuries in the space of just a few years, so it's only logical that there's something different about the work I have to do.
"But this does not mean I cannot cope with 90 minutes or more than one game a week -- otherwise there would be no point doing all I've done, would there?"