Dixon tore ligaments in his left ankle during a training mishap on Friday, when the power forward landed awkwardly on a teammate's foot after a marking contest.
It is unclear how long the 31-year-old will be on the sidelines for and whether he will have to undergo surgery.
The club will determine the best course of action for Dixon, whose left foot is in a moon boot, and Fantasia after consulting surgeons.
Fantasia has recovered from surgery on his left knee.
However, the former Essendon forward is having ongoing issues with his right knee.
Fantasia was restricted to 15 games in his first year at Port because of mid-season knee surgery.
Dixon played all 24 matches last season, booting 48 goals to finish the club's leading goal-kicker.
Port's 2021 campaign ended with a 71-point loss to the Western Bulldogs at Adelaide Oval, marking the second year in a row in which they were eliminated in a preliminary final.
The Power are set to begin this season with a match against Brisbane at the Gabba on March 19.
24°C