Italy captain Sergio Parisse is facing a month on the sidelines after sustaining a torn hamstring while on club duty for Stade FranÃ§ais.
Parisse lasted just eight minutes in his first game back after a four-week break due to calf and back injuries, as he was forced off the field early in Stade's 37-23 victory over Bordeaux-Begles in the Top 14 on Saturday.
The Azzurri skipper confirmed on his Twitter account that he was expected to be out for "three to four week" and that he had started therapy "with a smile" and was staying "positive".
The injury means the number eight will miss Stade FranÃ§ais's last fixture of the Top 14 regular season, when they visit Toulon needing an upset victory to have any hope of sneaking into the play-offs.
It is not yet clear if Parisse will be fit for Italy's three-match tour of the Pacific Islands in June when they will face Fiji, Samoa and Japan on consecutive weekends.