There really couldn't be more at stake at Cardiff's Principality Stadium today, with the victor of Joshua vs Parker expected to challenge America's WBC champion Deontay Wilder in the biggest fight of the 2018.
Joshua is also now a bona fide "stadium fighter", so much more used to the big occasion than Parker, and a near-80,000 crowd is expected under the roof of Wales' national stadium.
The losses signifying the intentions of both fighters to improve their speed and movement. I think were both going to be fast tomorrow night. "What I learned is that [Floyd] Mayweather is a technical fighter, but he's very, very good at building himself up outside of the ring". It depends who follows their game plan better.
"Mayweather, as great as he is, goes 12 rounds the majority of the time, and everyone claps and says how great the performance was, but because I don't knock my opponent out in two rounds it's a bad performance".
"I'm here for a war. I believe I can get to that level".
Parker's chin will likely decide early what type of fight this turns out to be.
"All these years United Kingdom fighters had to go to America and everyone had to spend a heap of money to go to Vegas".
"I got the offer to come to Sky Sports to be a commentator for the show. He's big, athletic. The one thing for him is the moment: if the moment is not too big for him he's got a shot". It doesn't faze us.
"I'm taking those belts back to New Zealand". I'm ready for anything.
I can see this going the distance.
Parker, sports a record of 24-0, 18 KOs, and comes from New Zealand bringing with him the WBO title when he travels to Joshua's home country to try and unify the belts.More news: Facebook adjusts privacy settings for users
More news: Brathwaite, Holder opt out of Windies T20 series in Pakistan
More news: Interstitium: New organ discovered in human body
It was gripping stuff, and Parker was feeling bold in the sixth round, with Joshua looking carelessly open at times, especially on retreat.
Parker made the big Brit wait for the traditional face-off but they had an extended and respectful handshake as they separated.
"Carrying around a bit of extra weight makes things hard", Joshua said.
A brass band for Anthony Joshua and a sipi tau and haka on the stage for Joseph Parker - today's weigh-in had something for everyone, including a surprisingly small 2.5kg weight advantage for the Englishman.
DAZN standardly costs €9.99 a month in Europe (Swiss pricing differs, as does Canadian) but there's also the opportunity to bag a free one-month DAZN trial which includes the fight. I stated this would be boxing finesse, and I stuck to my word and I controlled behind the jab, the counter punches.
The crowd had been warmed up by yet more banter between rival promoters Eddie Hearn and David Higgins, the New Zealander playing his part of cartoon-like villain to perfection and the boos rang out loud and long.
Sky customers can book the fight either with their Sky remote (by pressing "box office" or through the "Sport" menu) or they can book online here. It's going to be explosive.
Parker appears to be cutting a trimmer figure these days.
After the meal he spent around 30 minutes doing a question and answer session with them, plenty of emphasis being on his family life outside the ring.
"It's going to be a closer fight than anyone thinks".
He had his final light training session before heading to the weigh-in on a very cold Cardiff day where spring is struggling to make its mark.