Port Adelaide defender Esava Ratugolea is facing 12 months on the sidelines after suffering a sickening knee injury in the Power's 11.12 (78) to 6.16 (52) defeat to Collingwood.

Ratugolea was rushed to hospital on Saturday night and will undergo immediate surgery on a suspected ruptured patella tendon.

The 27-year-old was taken off on a stretcher after badly hurting his knee in a marking contest late in the third quarter.

It was a nightmare third term for the Power, who had already lost Jack Lukosius to a calf injury.

Utility Ewan Mackinlay also hobbled from the field with a suspected medial sprain in his knee while Ratugolea was being treated by medicos.

Ratugolea, a former Geelong tall, had enjoyed a stellar game with 10 intercept possessions before hurting himself.

"It's probably most likely 12 months," Port coach Josh Carr said.

"He's in pretty good form and marking the footy, so obviously disappointing and flattening for him and his family and us as a footy club."

Mackinlay will miss up to eight weeks, but Port are unsure on the extent of Lukosius' setback, medical staff wondering whether it could be swelling in his leg rather than a calf strain or tear.

The former Gold Coast ace, in his first game following two months sidelined with a groin issue, played a crucial role in Port attaining their early 19-point lead.

"He was playing really well in the first game back on the wing and using the footy well; he was one that could get some deep entries," Carr said of Lukosius.

Port, sitting 15th with a 4-10 record, will be forced to draw deep on their reserves ahead of next Saturday night's Showdown against Adelaide.