Gatland is after a career-defining moment: a landmark achievement that will allow him, regardless of how the remaining years of his career pan out, to enter the Pantheon.
Victory for the Lions will also strengthen their case to survive amid growing concerns their place in the rugby landscape is not as secure as it should be.
Hansen just likes winning because that's the expectation that comes with the All Blacks.
Unquestionably if the two men were distantly respectful to one another before the tour, they no longer are.
The two elder statesmen of international coaching have seen their relationship sour somewhat since the Lions were first picked in April.When the final whistle blows at Eden Park, there won't be much warmth when the two respective coaches shake hands.
For Hansen, that will be just fine. He hasn't set out to make an enemy and he no doubt found it curious that Gatland should even think there has been trash talk in the build up to this series.
To his ears maybe but to everyone else's All Blacks coach Hansen has been asked over the last few weeks questions about the Lions and answered them.
It has been standard fare. Or at least standard fare as far as Hansen goes. If he sees a way to help the All Blacks, he'll take it. He doesn't needle opposition coaches for the sake of it. He doesn't try to land cheap shots for the joy of headlines and personal glory - it's all part of a wider strategy to give his side some kind of advantage come the crunchy part.
He's twisted many a Wallabies coach into knots over the last few years, leaving the likes of Robbie Deans, Ewen McKenzie and now Michael Cheika second guessing their every decision.
The fact Gatland has interpreted much of Hansen's commentary and that of the New Zealand media as some kind of orchestrated personal attack, alludes not so much to a surprisingly thin skin, but to a much more potentially damaging frailty.
Hansen hasn't directly said it as such but the tone and implication, hints that he feels Gatland sometimes puts himself ahead of the team. That's a weak spot and as such every time Hansen has been asked about the Lions, he's brought up the style in which he thinks they will play.
Why? Because Gatland taks it personnally, reacts to it and seems to be rattled by the suggestion he has a particular coaching style known to one and all as 'Warrenball'.
And if Gatland is rattled it is good for the All Blacks. If Gatland is caught swearing under his breath as he was earlier in the tour, exasperated at having to continually defend himself and his love of Warrenball, then that, too, is good for the All Blacks.
"I didn't have any conversations about Gats," said Hansen on Thursday when he was asked if he was concerned that the build up to this series had been marred by the perception of bad blood between the respective coaches.
"I have just answered the questions you blokes have asked me. It would be really boring old press conferece if I sat here and said nothing. Warren a Gatland is a good coach.
"He's got his own style and he's selected a really good team and we have to go out and earn their respect as they have ours...which is why it is called a test match."
Gatland has understandably felt a little on the back foot since the Lions arrived in New Zealand. Their opening two games were poor and then when they lost to the Highlanders, he couldn't exactly counter punch Hansen.
But when the Maori were despatched in Rotorua and the Lions had two good Saturday performanced behind them, Gatland was in a better place to be more forceful and challenging of the All Blacks and Hansen.
And he obviously felt he needed to say something. To stand up for himself and have a crack back.
"I was surprised a little bit in terms of Steve Hansen," Gatland said. "Normally he's pretty calm but he's been doing a lot of press conferences in the last couple of weeks. I can only take that as a sign of respect that he's potentially a little bit worried."
Of course Hansen just laughed that off on Thursday, revealing his emotional state as: "Pretty cool, calm and excited. You guys who know me will know that I tell you all the time that worry is a waste of emotion.
"It is a wasted emotion becuase if the thing you are worried about has happened you need to fix it and there is no point in worrying about it.
"If it hasn't happened then get a plan so you don't have to worry about. It's good fedback from Warren. I appreciate it."
Trash talk or just talk, the distinction no longer matters. The only thing that does in respect to the two coaches is which one of them has done their homework best?
Which one of them has analysed most deeply, stategised most effectively and come up with the best plan?
