Former Manchester United star Nani admits his ACL injury is tough to take.
The 36 year-old moved to Australia this season to play for Melbourne Victory.
He posted to social media: "I want to thank the people who have been sending me messages of support over the last week.
"I am very sad and frustrated to have suffered this injury. There is nothing I would like more than to help the club recover from a difficult start to the season and to repay the fantastic support that the Melbourne Victory fans have shown me and my family since we arrived in Australia.
"I can assure you that I will work hard to recover as quickly as possible and return to the pitch.
"See you soon."