GEELONG has been dealt a blow with injured pair Cory Gregson and Josh Cowan set to miss the rest of the season after undergoing surgery.

Gregson has been sidelined by a navicular injury in his foot since the middle of last season, which was his second in the AFL. 

The club said the injury was failing to heal, with the small forward set for another six weeks in a moonboot before he can run again in around three months.

Cowan's unlucky run with injury throughout his career has continued after the club decided surgery was the best option with his Achilles tendon. He is expected to be out of action for 10-12 weeks.

Having been drafted in 2009, Cowan has played just 16 games in his career after significant fitness battles. 

"Obviously this is disappointing for the players and our team," said Cats football manager Steve Hocking.

"Both procedures will allow the players to move forward with the club's medical team on a rehabilitation plan."