FACING his first ever hamstring injury, Geelong superstar Patrick Dangerfield is unsure how long he will be sidelined.

The 2016 Brownlow Medallist suffered the injury late in the first quarter of Sunday's pre-season loss to Essendon.

"I will wait until (Tuesday) and see how it is, it feels pretty good," Dangerfield said at Geelong's headquarters on Monday.

"I've never done a hammy before, so without having done one, it's hard to say where it's at."

The injury puts Dangerfield in significant doubt for the Cats' March 25 season opener against Melbourne at the MCG.

Fellow Geelong star Gary Ablett has also missed the Cats' two pre-season games with a hamstring injury, but is more likely to be ready for round one.

"It's not ideal – that being said, there are far more people in worse situations than I am," Dangerfield said.

"You need a little bit of perspective I think."