Paddy McGrath will not be available for Ardara's club championship campaign and is set for a lenghty period out of football.
The Donegal Democrat are reporting McGrath suffered a cruciate injury during the second half of Donegal's defeat to Mayo in Castlebar last Saturday.
A scan revealed the extent of the injury which is expected to keep the 30 year old out of action for up to ten months.
It's the second time in his career McGrath has had to deal with a cruciate injury.
A few years ago he suffered damage to the cruciate. He did not have surgery at the time but returned to win two more Ulster titles with Donegal.