Having recovered to topple the Tigers and Storm in thrilling fashion, the Warriors might be forgiven for thinking they have already achieved plenty. They will, however, be a long time forgiving themselves if that mentality proves their undoing.
"I had a lot of people come up to me and say 'we don't care about the GF, as long as you beat the Bulldogs'," said Mateo of 2009, when the Eels beat their arch rival in a hugely hyped Battle of Sydney grand final qualifier.
"We all wanted to win it, but I guess there was a feeling it was a good thing getting there. We have spoken about that. We don't want to be happy to be there. We think we are good enough to win it."
Coach Ivan Cleary didn't think getting his team to switch from being desperate to reach a grand final to desperate to win it would be difficult.
"I have no interest in coming second," Cleary said.
"It is not hard to work out when you get up every morning where you want to finish - that is not in the grand final, it is winning it. But we never set it out as a particular goal, we have just arrived here based on what we have been able to do.
"It is absolutely fantastic to get the opportunity to experience all this but, really, it is about having the opportunity to become champions, not a side show."
Despite a transtasman surge of support the Warriors are still firm underdogs.
"No one expected us to beat the Tigers and no one expected us to [beat the Storm]," Mateo said. "Let them keep doubting us."
Having joined the Warriors after the Eels' 2010 campaign, Mateo never doubted the move - not even after those three season-opening defeats.
"Never mate. Those first three games, we didn't win them but we played some good footy. And looking at the squad the club had, it was really promising."
The Junior Warriors and feeder club Auckland Vulcans also contesting grand finals on Sunday supports his view the club is stocked with talent.
Often described as a special player for his prodigious offloading and line-breaking ability, Mateo insists there is, in fact, nothing too special about this Warriors team.
"It's just been dirty, ugly footy. Going forward, completing sets and taking our opportunities when they come. That is what we have been doing for the last two weeks and, hopefully, we can do it again this week.
"Manly are a great team, they have got strike across the whole field. But it is just another game you have to grind out. They have some hard heads in that pack and they will get even harder with Glenn Stewart coming back.
"But if we just worry about ourselves, play our brand of footy and keep level headed, then I think we can win it."
TAB ODDS
* Manly $1.55
* Warriors $2.35
