The light-middleweight division will have a new undisputed world champion crowned this weekend when Jermell Charlo and Brian Castano meet at the AT&T Center in San Antonio.
Charlo is the favourite to end up holding all the four major belts, having added the IBF and WBA versions to the WBC title that was already in his possession with an impressive stoppage victory over Jeison Rosario last time out.
The American – identical twin brother of middleweight world champion Jermall – needs just the WBO strap now to complete the set. Castano holds that gold, the Argentine fighter yet to lose as a pro after an outstanding amateur career.
His CV in the paid ranks includes 17 wins and a solitary draw, which came against Erislandy Lara back in March 2019. The 31-year-old has a reputation for being proactive in terms of his work-rate and punch output, a style that should make for entertaining viewing once the first bell sounds.
Texan Charlo has the benefit of home advantage as he bids to clean up in the division, though Castano is not concerned about stepping into his opponent's back yard on Saturday.
"He has all the pressure on him being in his home state," Castano said at the media day during fight week. "I've been training so hard for nine months and I'm comfortable as the underdog. I always come in as the underdog, so I don't feel any pressure."
For his part, Charlo has shown no signs of taking his next challenge lightly, describing Castano as a "great fighter" in the build-up. There is speculation a move up in weight could be in the not-too-distant future for the 31-year-old, but his only focus is on realising a childhood dream.
"I wanted to be an undisputed champ since I was a child: that's always the highest you can get in boxing," Charlo said.
"To have this opportunity to see these moments, I want to say thank you to all my team and everybody that has pushed forward for this."
While it may go against his instincts, Castano should be wary of rushing in against a fellow champion who has won three on the spin by knockout since suffering a first career loss in December 2018.
Charlo was beaten on points by Tony Harrison to lose the WBC crown, though 'Iron Man' demonstrated his mettle by coming through a rematch a year later to reclaim the title.
Last September, Rosario was dropped three times before being stopped in the eighth round, improving Charlo's record to 34-1.
Castano needed the scorecards to settle his clash with Patrick Teixeira in February of this year, a unanimous verdict in his favour - one judge gave him every round - securing the belt and, in the process, paving the way for this huge opportunity.
TALE OF THE TAPE
Height: 5ft 11ins (180cm)
Professional record: 34-1 (18 KOs)
Major career titles: IBF, WBA, WBC light-middleweight
Height: 5ft 7.5ins (171cm)
Weight: 153.25 lbs
Professional record: 17-1-0 (12 KOs)
Major career titles: WBO light-middleweight