Grant, who has made nine A-League appearances this season, tore the ligaments off the bone after going over on his ankle during training on Friday 12 February.

After being sent for immediate X-rays and with the full extent of his injury now known, the 19-year-old underwent surgery where he had a screw inserted to re-attach the ligaments.

He will be in boot for the next 8-10 weeks before commencing a physiotherapy and rehabilitation program with Sydney FC staff.

 "I went into a tackle and went over my ankle and heard a strange noise so I was worried," Grant said.

"After I found out what was wrong it was pretty devastating but there is not much you can about it.

"The club staff have been really great and a lot of the boys have spoken to me, told me to stay positive and gave me advice. That really helps."

Grant was an integral member of Sydney FC's title winning National Youth League side last season, making his A-League debut in December 2008.

He also represented Australia in the 2009 FIFA U20 World Cup in Egypt.