Boxing has changed. HBO and Showtime are gone. Once dominant fighters like Roy Jones, Bernard Hopkins, Andre Ward, and the Klitschko Brothers have left the arena. Big fights are gravitating to Saudi Arabia.

In recent years, through it all, there has been one constant – Canelo Álvarez.

On Saturday night, Canelo won a unanimous decision over Jaime Munguia in a scintillating fight at the T-Mobile Arena in Las Vegas. For those who like their boxing straight up, the win solidified his status as the signature fighter of this era.

Canelo turned pro in 2005 at the tender age of 15. Nineteen years later, he has crafted a 61-2-2 (39 KOs) record which includes victories over Gennady Golovkin (twice), Danny Jacobs, Sergey Kovalev, Billy Joe Saunders, Caleb Plant, Shane Mosley, Miguel Cotto, and Erislandy Lara. He holds all four major 168lbs belts and has won world titles at weights ranging from 154 to 175lbs. Forbes ranks him as the fifth highest-paid athlete in the world.

The road to Canelo-Munguia was long and winding. Last September, Canelo dominated Jermell Charlo in the first fight of what was believed to be a three-bout contract with Premier Boxing Champions. That encounter was on Showtime-PPV and generated an estimated 700,000 buys. Charlo fought to survive, not win, and said afterward, “I’m proud of myself: he ain’t knock me out.”

Then, on 17 October, Paramount announced that it was closing Showtime’s sports department and would no longer televise boxing. Next, on 7 December, PBC and Amazon announced that Prime Video would distribute PBC pay-per-view events on a non-exclusive basis and also stream a series of “free” PBC Championship Boxing fight cards to be shown only on Amazon in the United States.

Amazon’s goal is to build a live pay-per-view platform for diverse events. Its relationship with PBC is an early foray into that world. It has no interest in playing the sort of role that HBO and Showtime played in boxing. It will take and distribute the product that it’s given.

The deal gives PBC a huge platform for boxing. Prime Video has more than 150 million subscribers in the United States. But to date, Amazon hasn’t provided much of a marketing push for PBC’s pay-per-view fights. And the “free” cards have yet to kick in.

It was widely assumed that Canelo would be a key player in PBC’s pay-per-view shows on Amazon. Then, on 26 February, it was revealed that PBC was letting him go after one fight of their contract rather than pay his previously agreed-upon contractual minimum. Whether that was because the two sides couldn’t agree on an opponent is unclear. One rumor was that Canelo’s attorney demanded that $35m be placed in escrow to cover his client’s next purse under the old agreement and PBC declined.

However in March it was announced that Canelo would return to PBC on a new one-fight contract to face Munguia in a bout that would be available on pay-per-view through Amazon and other platforms including DAZN (which has a deal with Golden Boy, Munguia’s promoter).

Munguia (now 43-1 with 34 KOs) hadn’t had the hard inquisitors on his record that would raise him to elite status. But in his most recent outing, he’d knocked out John Ryder (who went the distance in a losing effort against Canelo last May). He’s 27 years old and is trained by Freddie Roach.

Adding a subplot to the proceedings, Canelo was once promoted by Golden Boy. But he left the company several years ago and has feuded bitterly with Golden Boy CEO Oscar De La Hoya ever since. During the buildup to Saturday’s fight, Canelo kept his distance from De La Hoya, telling reporters, “I’m not interested in being a friend to him. I’m good where I am. I have nothing to do with him. I wish all the best for him, and that’s it. But I don’t want him in my life. I don’t want him near me or close to me. I don’t want those kinds of vibes in my life.”

That said; Canelo-Munguia was the second opportunity in two weeks for a Golden Boy fighter to score a huge upset victory. On 20 April Ryan Garcia, Golden Boy’s most marketable fighter, had decisioned Devin Haney in a much-commented-upon, high-profile bout.

Canelo-Munguia was a nice match-up but not as big an event as might have been expected for a fight on Cinco de Mayo weekend between two Mexican fighters, one of whom is arguably boxing’s biggest star. One fight-scene veteran recounted looking across the media center during fight week, seeing former HBO blow-by-blow commentator Jim Lampley (now the mainstay of PPV.com’s fight coverage), and thinking, “There’s a buzz but not the electricity there was when Canelo was fighting on HBO.” The crowd of 17,492 on fight night would be well short of a sellout.

Canelo was the heavy betting favorite. The fighters expressed mutual respect for each other. The last Mexican fighter prior to Munguia that Canelo had faced was Julio César Chávez Jr in 2017. Before that, one had to go back to Canelo v Alfredo Angulo 10 years ago.

“The fight might divide Mexico,” Munguia offered. “But in the end, it will unite Mexico because everyone will be watching the fight.”

At the final pre-fight press conference on Wednesday, the bad blood between Canelo and De La Hoya boiled over. Canelo called De La Hoya “a fucking asshole” and accused him of stealing from his fighters.

“He seems to have trouble remembering who helped him become a true global star,” De La Hoya responded. “… Yes, there were times that work was not my priority based on my mental health, which I had neglected for so long. But that doesn’t change the fact that Golden Boy built Canelo Álvarez, period. The company you fought under has always had one name and it’s mine, so put some fucking respect on it.”

Later that day, Golden Boy suffered a blow when it was reported that before and after his fight with Haney, Garcia had tested positive for Ostarine, a banned performance enhancing drug.

When fight night arrived, the 10-bout undercard was long and dreary. Then the main event began and a drab night turned to gold.

The crowd was evenly divided. Munguia controlled round one with his jab. Canelo began fighting more aggressively in round two, and his opponent was willing to engage. Munguia was a bit faster, kept the pressure on, and was landing solid punches. Canelo would have to walk through fire to win. Then, with 40 seconds left in the fourth stanza, a right uppercut sent Munguia crashing to the canvas for the first time in his career.

In round five, Munguia came out firing again. The crowd was roaring. It was a war. Canelo seemed to enjoy the test. His body shots started to take a toll. But Munguia hung tough and rallied in round eight. Once again, Canelo accepted the challenge and fired back.

It was a tense, all-action firefight with two tough, courageous fighters giving everything they had. Munguia wouldn’t let Canelo rest. The champion began to tire. But he’s a complete fighter and took the late rounds on skill and technique, picking his spots and continuing to land sharp blows. Munguia went for the knockout in round 12, and Canelo stood his ground.

I scored the bout 116-112 for Canelo (7-4 in rounds with one round even). Judges Steve Weisfeld (115-112) and David Sutherland (116-111) straddled those numbers, while Tim Cheatham’s tally was 117-110.

Responding to a post-fight question in the ring, Canelo declined to rank himself in the pantheon of great Mexican champions. But he did offer this thought: “I’m the best fighter [in the world] right now, for sure.”

• Thomas Hauser’s email address is thomashauserwriter@gmail.com. His most recent book – a memoir titled My Mother and Me – is now available in stores. In 2019, he was selected for boxing’s highest honor – induction into the International Boxing Hall of Fame.