Ospreys wing Hanno Dirksen will miss the start of the 2016-17 season after undergoing knee surgery.
The 25-year-old suffered the injury during Ospreys' win over Cardiff Blues at the Principality Stadium in April.
"Hanno had an ACL reconstruction last week," Ospreys medical performance manager Chris Towers said.
"He is now looking at a lengthy rehabilitation period running into next season before we can look at an accurate return to play date."
South Africa-born Dirksen signed a new three-year Ospreys contract in May 2014, keeping him at the Liberty Stadium until the end of the 2016-17 season.