Lincoln McCarthy will undergo surgery in Sydney this morning on his troublesome left foot.

The promising small forward suffered a stress reaction in a ligament across the top of his foot in early December and after consultation with Dr Kim Slater two weeks ago, will have surgery today which is expected to keep him out for up to five months.

“It’s the cartilage that lines the joint where your leg bones come down and your foot actually joins in,” General Manager of Football Steve Hocking told the K-Rock Football website.

“He’s got some corrosion in the area. It’s like a flap that’s hanging within that cartilage.

“What they have to do is get in there and irritate that cartilage, and that generates blood flow and regenerates it.

“The lack of blood flow into that region is a real concern for anyone who suffers from a fracture within that bone.”

This is the third major injury for the 21-year-old who missed all of 2013 with a navicular bone issue and was sidelined for 12 weeks in 2014 with a back injury.

Hocking assured Cats fans that McCarthy is remaining mentally strong despite the setback.

“He’ll work his way through it and we’ve got systems in place that will support him accordingly.

“He’s got a contract to run for next year, so that’s not a concern for him either.”

McCarthy has played five AFL games since his debut in 2012 including the Cats semi-final loss to North Melbourne last year.