Geelong are likely to be without key defender Esava Ratugolea for the coming weeks due to a hamstring injury.

Ratugolea was subbed out of Saturday's loss to the Giants in the third quarter after recording a hamstring issue following a contest on Geelong's last line, with the Cats forced into making their tactical change and bringing Mitch Knevitt into the game.

The injury is expected to see Ratugolea miss his side's Round 12 clash with the Western Bulldogs, which will be followed by a timely bye that could help the injury-stricken club ahead of their run toward September.

Speaking after the seven-point loss at home, Geelong coach Chris Scott said early signs suggested Ratugolea may have suffered a hamstring strain.

"I think it's more than (tightness) unfortunately," Scott told reporters.

"Hopefully this injury's on the minor end and he only misses a small amount of footy."

Swingman Jack Henry also required attention from club trainers for a shoulder injury sustained in the opening term, with the athletic Cat down in the rooms at the first break before returning to the field midway through the second quarter.

MELBOURNE, AUSTRALIA - MAY 07: Esava Ratugolea of the Cats and Marlion Pickett of the Tigers in action during the 2021 AFL Round 08 match between the Richmond Tigers and the Geelong Cats at the Melbourne Cricket Ground on May 07, 2021 in Melbourne, Australia. (Photo by Michael Willson/AFL Photos via Getty Images)

The Cats are already without Patrick Dangerfield (hamstring), Mitch Duncan (hamstring), Max Holmes (knee), Cam Guthrie (toe), Gary Rohan (hamstring), Rhys Stanley (eye) and Sam Menegola (knee), among others, for the time being.

Dangerfield is eyeing a return to face the Bulldogs at Marvel Stadium next weekend, while several others are in line to return after the club's bye.

Scott spoke on the "obvious reasons" for his side's on-field frustrations, but said the Cats won't be making any drastic changes to their system after a third successive loss.

"It was a really frustrating night and we do feel like we are chasing our tail a little bit, but I don't feel like that's a unique position within the competition at the moment," Scott said.

"We're not hiding away from the fact that we're not playing as well as we could, but we think there are some pretty obvious reasons for that.

"We don't think we're in the position where we need to throw out what we're doing and start all over again."

The Cats sit ninth on the ladder with five wins from their opening 11 matches.