Had the Warriors achieved more success in recent times, he would be held in similar regard to Richie McCaw.
He's almost certain to be named Warriors Player of the Year for the fifth time in seven seasons, which reflects both his remarkable consistency and the lack of grit and ambition among his team-mates.
The 30-year-old always puts the team first but you wonder how much more he can give, and how many more times he can watch players around him benefit from his efforts without having the desire and fortitude to match it with their own.
"We are in a team sport but it is very much individual as well," Mannering told the Herald on Sunday. "You have got to want to do your part for the team. I'm not saying that is the case here but for sure there are things that take longer to stick with some players than others and I haven't got an answer for it."
Mannering came through a different era, a different generation. It was before the social media craze, before the under-20 competition and before the hype and adulation that seemed to be thrown on every new young player.
"Maybe it's easy to get caught up in things but you can lose perception of how lucky we are," said Mannering.
"Playing professional sport for the only NRL team in New Zealand, you can get caught forgetting what position you are in. We are all so fortunate to be here."
Mannering doesn't say much publicly - even in his six years as captain, he wasn't that effusive - but he has a strong presence behind the scenes and what he does offer makes a lot of sense and should be contained in a manual for aspiring NRL players, and particularly young Warriors.
"As a team, we are inconsistent, and as individuals, we are inconsistent," said Mannering. "In the NRL, that should be your primary objective, to be consistent and the difference between your best game and worst game is close."
"It's not about how many tries you can score, or all that other stuff, or how good you can be. It's about getting the win each week, whether it is pretty or ugly, it doesn't matter. It is disappointing that hasn't been a common theme and we need to create an environment where consistency is the norm."
Mannering is always held up as the aspirational example of the kind of attitude and mental toughness that should permeate through the club.
But there was no secret formula. He came to the game late, not playing league until he was a teenager, and while his rise was swift, it was far from smooth.
"It's about being thrown in the deep end and seeing if you can swim," said Mannering. "At the start, I was always in the deep end, I hadn't played much. I was playing against men in the Bartercard Cup - thinking 'shit, I'm out of my depth' - but then you get used to that.
"Then coming up here and training, that was a step in itself, then you adapt to that. Then playing NRL.
"Thinking back now I was nowhere near ready to play first grade but I had an opportunity and I tried to do everything away from the field to make sure when I am on the field, I could do a job. I managed to just survive that first year."
Mannering has thrived since and been one of the players who has held the team together this past decade. But his long career (278 games) means he feels the hard times more than most.
"It's frustrating for us as a club and our supporters over the last six years and what they have seen," said Mannering.
"As a player, I'm so disappointed for them. We know they cop so much shit for supporting us and we are still down there [outside the eight]. That's who I feel sorry for the most, not myself or my team-mates. It's the ones who turn up every week and are there to cheer you on and we don't deliver."
