Geelong coach Mark Thompson candidly admitted 'something is wrong' with the Cats after their finals prospects were rocked by a 14-point loss to the Western Bulldogs at Etihad Stadium on Friday night.

While the scoreline was tight after an enthralling third-term fightback by the Cats and a final-quarter wrestle, the defeat highlighted more problems in a team once favoured to win the flag.

Thompson was particularly angered by a second term that allowed the Bulldogs to skip out to a 19-point lead.

"The second quarter was horrible to watch, to be involved with," he said.

"I think we played better in the third quarter. But to play so poorly in the second and then much better in the third, tells you something is wrong. That's my concern."

Another concern was a hamstring injury to key forward Paul Chapman, although Thompson said he could yet play against Fremantle next week.

Thompson said the coaches and medical staff had debated whether he should go back on after leaving the field - for good - in the third term.

"He is not the sort of player you should be messing with. He is an important player," he said.

While the Cats are assured of second spot on the ladder, issues abound for Thompson and his selection committee.

He said James Kelly, Steve Johnson, Tom Harley and perhaps Brad Ottens would be available for selection next week, with the club's inconsistency of late due to an unstable side.

"We are making five changes every week, so we are not going to outsmart ourselves," he said.

"If we can get the same team out on the park, then I think we can play much better."

That will need to happen as the Cats have dropped four of their past eight matches and appear ripe for the picking come September.

"It has been difficult. I don't think we could ever see it coming that we could struggle as much as we have in games in such a short time," Thompson said.

"They have been up for a long time."

"The secret is, with one more round to go, is to open up the can and just get them to start enjoying their footy, get them to start working incredibly hard on a consistent basis."

"I just have to keep pushing that message to the players."