Marty Taupau is used to striking fear in opponents but the Sea Eagles hard man admits he went through some "scary" times after he copped a high tackle from Warriors forward Jack Hetherington.
The Panthers loan forward was sin binned and later suspended for four games for the swinging arm, while Taupau was removed from the game after failing an HIA then missed the following week.
"Scary, I'll tell you that," Taupau said.
"It's the first time I've ever been knocked out cold. I don't remember at least 20 or 30 minutes post-hit.
"After that it went pretty much downhill. I think it was amnesia, post-traumatic amnesia I think is what it's called. Not ideal. Deteriorated a little bit but back on my feet and back at work."
The symptoms over the subsequent days included constant headaches, he added.
"From the night I copped the knock up until Monday, constant headaches. It was pretty scary from the moment I got up, day-to-day things, it was constant headaches which is what was really scaring me and there was a few things I was forgetting as well. Just short-term memory.
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"It certainly puts a lot of things into perspective playing rugby league which is one of the most brutal sports in the world."
Taupau said he had no hard feelings against Hetherington, describing the shot just as something that happens in footy.
"That's just the nature of the sport. People could deem it as there's malice in it or careless, it's happened to the best of us. Unfortunately I was on the end of that big knock. I'll just take it on the chin – literally – and just move on.
"I'm glad I don't sit on the judicial panel. He's copped four weeks which is probably a way for him to reflect. I've probably been on the end of that as well."
Taupau added he had spent plenty of time thinking about head knocks and life after footy even before the recent incident.
He also revealed he went above and beyond the club's already-stringent concussion management protocols, seeking out a CT scan himself to be on the safe side.
"I was pretty worried about the knock and all, and decided to not play last weekend," he said.
"I did what I could to get further diagnosis on what had happened, consulted with our doctor and physio and opted to get a CT scan to make sure there was no brain bleed whatsoever.
"Results came back really positive and I've done further tests as well, it's all come back positive as well. I feel pretty happy and confident I'll be back to my best this week for the boys.
Taupau will return to a Sea Eagles side sitting in 10th place and desperate to get a win over the eighth-placed Rabbitohs on Saturday as they target a late-season push towards the finals.