MELBOURNE, AUSTRALIA - NOVEMBER 06: Charlie Curnow takes part during a Carlton Blues AFL training session at Ikon Park on November 06, 2019 in Melbourne, Australia. (Photo by Darrian Traynor/Getty Images)

Carlton star Charlie Curnow has reportedly suffered a setback with his knee injury, and is expecting to go under the knife once again.

According to 7NEWS, Curnow sought out advice in the past 24 hours on his injury, and more surgery is “looming”, which could see him in doubt for a round one return.

Curnow was set to return to running before Christmas, but that now looks unlikely if surgery is on the table.

The 22-year-old suffered a knee injury in early October, and had surgery which was a ligamentous repair to stabilise the patella.

Earlier this month, Curnow told 7NEWS he planned to be up and running by mid-December.