PORT Adelaide defender Hamish Hartlett recovered from a sickening head knock to be one of the Power's best in their 34-point loss to Geelong at Adelaide Oval on Saturday night.

Hartlett collided with Geelong superstar Patrick Dangerfield in the second quarter and had to be stretchered off the ground.

He had blood pouring from his face, but passed a concussion test, had his head bandaged and returned to the game at the start of the second half.

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Hartlett had 18 disposals after half-time and didn't show any effects of the gruesome incident.

"Clearly, he was okay to come back on," Power coach Ken Hinkley said. "Sometimes, (like) what happened with Hammer, the hit and the blood makes them sometimes a lot worse than some of the other simple head knocks.

"Luckily enough for us, Hammer was really clear and right to go and cleared by the doctors and he come on and played like he was fine."

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In 2016, the Power was fined $20,000 – with $10,000 of that suspended until the end of this season – for failing to follow AFL regulations when Hartlett was assessed for a head knock against Hawthorn.

Under the regulations in 2016, Hartlett should have been off the ground for a 15-minute exclusion period to allow the club doctor to access vision of the incident. However, he returned to play after five minutes because the Power failed to notify the AFL's interchange official that a head injury assessment was being undertaken.

Hinkley said there was no such issues this time.

WATCH: Ken Hinkley's full post-match press conference

"He would have got checked properly," Hinkley said.

"He was absolutely 100 per cent clear down in the change-rooms and everyone, doctors and Hamish himself, had no problems at all about coming back."

The Power's forwards struggled to take clean grabs close to goal against the Cats, with only four marks inside 50 from 51 inside 50s.

"We're not marking the ball as well as we would like in our forward 50," Hinkley said.

"Some of the stuff we were going forward with, it looked like we were going to get it, but we found a way not to.

"We're not in terrific form in that area of the ground, but we're not in terrific form as a team at the moment, but how quickly it does change.

"It goes from today, bad, then we're ready to go again, because the season doesn't allow you to be out of form for a long period of time."

Hinkley hoped midfielder Tom Rockliff would be available to face North Melbourne at Etihad Stadium next Saturday.

Forward Todd Marshall (concussion) and defender Jasper Pittard will also likely come into calculations, while Sam Powell-Pepper's availability depends on the result of an ongoing AFL investigation.