Oleksandr Usyk, Murat Gassiev, Mairis Briedis, and Yunier Dorticos will put their cruiserweight world titles on the line in two semi-finals worth millions of dollars.

World Boxing Super Series promoter Kalle Sauerland tells Business Insider that all four fighters are "brutal" and "frightening."

The semi-final winners will contest the tournament final in the summer and the champion could end up challenging Anthony Joshua for the heavyweight belts in the future.

Sauerland describes his tournament as the UEFA Champions League of boxing and has managed to break new ground in 150 territories, brokering TV deals worth millions.

The cruiserweight winner of the World Boxing Super Series, a groundbreaking $50 million tournament, will be "a legend" who could eventually challenge Anthony Joshua for the heavyweight boxing world title.

That is the view of groundbreaking boxing promoter Kalle Sauerland who recently told Business Insider that the four cruiserweights competing in the upcoming semi-finals are "brutal" and "frightening" fighters.

The semi-final winners will meet in a lucrative final in the summer and the last man standing will be the undisputed cruiserweight world champion, a multi-millionaire, and a credible challenger to Joshua, a heavyweight who is fast becoming the face of boxing in the post-Floyd Mayweather era.

The Fight of the Year

The semi-final brings together four fighters who have a combined record of 85 wins and no losses. That's right — every fighter in the final four is undefeated. With 57 knockouts between them, they all pack a punch, too.

WBO cruiserweight world champion Oleksandr Usyk and WBC belt holder Mairis Breidis contest the first semi-final in Latvia on Saturday, January 27. The following weekend sees IBF world titlist Murat Gassiev and WBA ruler Yunier Dorticos trade blows in Russia.

When Business Insider first spoke to Kalle Sauerland last year, he tipped Usyk for success. He even told us that he ran a poll that showed 82% of people had picked Usyk to "win the whole thing."

Usyk blasted past Marco Huck, the greatest and most decorated cruiserweight since David Haye, in a tenth round quarter-final slaughter last September.

You can watch the highlights right here:

#TBT to Usyk stopping Huck in our opening quarter-final in September! 💥



📅 Date, venue & ticket news for #UsykBriedis coming soon!

🎟️ Sign-up for Ticket Alerts here: https://t.co/oredfUincr



🏆 #AliTrophy pic.twitter.com/xSiwWby9Rt — WBSuperSeries (@WBSuperSeries) November 30, 2017

Usyk's thumping victory enhanced his tag as favourite. However, Sauerland argues that the other fighters also excelled en route to the semi-final stage.

"Usyk is an Olympic, European, and world champion boxer," Sauerland recently told BI. "And he was a world champion after very few fights as a pro. He's an absolute superstar but has unknown quantities. The other guys don't as they have come through and passed tough examinations.

"Breidis, Gassiev, and Dorticos all enjoyed strong performances or strong knockouts in the quarter-finals. The way Gassiev dispatched Krzysztof Włodarczyk, who has been many times world champion, was brutal! Dorticos was also frightening [against Dmitry Kudryashov in the quarter final]."

Dorticos' crushing second round win over Kudrashov can be seen here:

This is great... How it feels to be in the winning corner!! 👌



The Team Dorticos view for @YunielDorticos' 2nd round KO of Kudryashov! 💥#DorticosKudryashov ➡️ #GassievDorticos 🏆 #AliTrophy pic.twitter.com/87z0r60cPT — WBSuperSeries (@WBSuperSeries) November 22, 2017

"You'd be a fool to put all your money on Usyk [to be World Boxing Super Series cruiserweight champion]," Sauerland said, pointing out that the other combatants cannot be overlooked. "Gassiev versus Dorticos on February 3 in Sochi could be an early contender for Fight of the Year!"

For Sauerland, what will separate the winners from the losers "comes down to moments" and "the ability to dig deep."

He says that despite Usyk's pedigree as 2012 Olympic champion and as current WBO cruiserweight champion, he "hasn't had to dig deep yet." Usyk may have credible victories over former world champions Krzysztof Głowacki and Marco Huck but how he reacts when he is up against a fighter who challenges him is still largely unknown.

"Dorticos also hasn't had to dig deep yet but what he does have is frightening power," Sauerland said, adding: "Breidis dug deep as he endured a nerve-wrecking 12 rounds with Mike Perez in his quarter-final. Even Gassiev had to dig deep before he entered the World Boxing Super Series as he overcame Denis Lebedev for the IBF cruiserweight world title in 2016."

The World Boxing Super Series champion will make history

Every fighter in the semi-final is a world champion. Each semi-final winner will annex the loser's belt. The final will therefore see two double cruiserweight champions fight each other.

No fighter in the history of cruiserweight boxing has held all four of the major titles at the same time, but the World Boxing Super Series winner will do just that. The winner will have won all of the major world title belts, the World Boxing Super Series title (the Ali Trophy), multi-millions of dollars, and will have secured a massive legacy.

"The overall winner will have cleared out the entire cruiserweight division," Sauerland told Business Insider.

So, having vanquished a who's who list of elite cruiserweights, what could possibly be next for the undisputed world champion?

As the cruiserweight limit is 200 pounds (90.7 kilograms) it is not too big of a leap to move to heavyweight (no weight limit) just like elite fighters like David Haye and Evander Holyfield have done in previous decades.

The World Boxing Super Series champion could be a future opponent for IBF and WBA heavyweight world champion Anthony Joshua. Getty Images

Here, a massively profitable fight against the self-styled Gypsy King Tyson Fury, American knockout artist Deontay Wilder, or world champion Anthony Joshua could be made in the next 12 to 18 months.

Is that what is in store for Usyk, Breidis, Gassiev, or Dorticos? Is the eventual World Boxing Super Series champion a future opponent for Joshua?

"Breidis has already fought at heavyweight," Sauerland explained, a nod to the fact that it could well be on the cards. "Everybody's talking about Usyk stepping up to heavyweight. These are big, big guys but Joshua is an even bigger guy.

"If it is Usyk who steps up he can rely upon his technical ability. The others, the punchers, all have that punch [that can vanquish an opponent] and can follow former champions like Haye and Holyfield who successfully stepped up to heavyweight in the past."

Regardless of future endeavours, Sauerland argues that the World Boxing Super Series champion will have secured a clear legacy. "Whoever wins the World Boxing Super Series is automatically a legend."

A 'Champions League-style product' for boxing

Kalle Sauerland has increased visibility into 150 territories, brokering TV deals worth millions. World Boxing Super Series screenshot

The World Boxing Super Series champion will become "a legend" because it's rare when fighters unify all of the four major championships. At cruiserweight, it has never been done.

The fragmented nature of world championship boxing means that the WBO, WBA, WBC, and IBF world titles could be held by four separate fighters, like it currently is at cruiserweight.

Unification fights, when two world champions meet in one fight, are uncommon. However, Sauerland's tournament has broken ground as it has forced participants into an easy-to-follow competition format.

Sauerland thinks the World Boxing Super Series is the closest thing boxing has to the UEFA Champions League in football.

He may be right. After all, the calibre of fighters involved, combined with the high-quality production Sauerland has overseen from each show, has seen him increase visibility of the product into twice as many territories.

"We have deals where we are visible in 150 different countries," Sauerland said. "This is up from 60 to 90 from the first event [the Usyk v. Huck quarter final last year].

"We've grown TV deals in a very good eight figure region. We're talking millions. But we have gone for a soft line on sponsoring."

Considering there is $50 million in prize money at stake, combined with production costs on a fight-to-fight basis, it seems surprising that Sauerland has gone for a "soft line" in sponsorship rather than seek at least eight deals, which is the norm in the wider combat sports industry.

"We are not looking for classic partnership but strategic partnerships, And have been in advanced discussions with two or three big companies," he said. "We want to retain the feel we have. The look and feel of the ring-walks, the productions, the shows. So we're doing that strategically, rather than having 15 different emblems plastered across our brand.

"This is more in line with a Champions League style product."

Like the Champions League in football, the World Boxing Super Series has brought together multiple champions from a number of divisions/countries.

After tonight, we may have a greater idea of who will lift the Ali Trophy at the end of the season.