Terence Crawford v Errol Spence Jr: WBO champion aims to prove he is 'best fighter in world'

Terence Crawford (R) has a perfect record from 39 professional fights, winning 30 of them by knockout

Terence Crawford says he will prove he is the "best fighter in the world" when he takes on Errol Spence Jr in their undisputed welterweight fight on Saturday in Las Vegas.

WBO welterweight champion Crawford, 35, challenges WBA (Super), IBF and WBC champion Spence aiming to become the first male fighter to win undisputed titles in two divisions.

A fiery news conference was taken over by heckling from each fighter's team, drawing out a passionate speech from the usually reserved Crawford.

"This is the Terence 'Bud' Crawford era. This is my era," he said.

"Everything about Terence Crawford is better than Errol Spence Jr. When you look at everything I do in the ring, it is better than Errol Spence Jr.

"Come fight night, I will be proving each and every one of the doubters wrong, once again, that Terence Crawford is the best fighter in the world. Not taking anything away from Errol Spence Jr but Terence Crawford is the better fighter."

• Bunce column: A brilliant fight, but Spence-Crawford lacks stardust

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After a relatively amicable build-up, tensions ran high between camps inside the T-Mobile Arena on Thursday in Las Vegas.

There was more needle between the fighters and their opposing teams than with each other.

Trainers Derrick James and Brian 'Bomack' McIntyre clashed over their respective coaching credentials, prompting furious heckling from their gathered teams in the crowd.

Spence, the WBC, WBA (Super) and IBF belt holder, said the fight would be a "Crawford boil" - telling his opponent he was "too emotional". Crawford spent most of his time telling Spence's team to be quiet.

"I am going to win because I am the better fighter. I am going to break him down and break his will," Spence said when he finally had the chance to speak.

"That my skills are superior. He's talented, but we're talking about skillset.

"I do have great stamina, I do have great fundamentals - I don't just have talent."

Can Spence-Crawford leave a lasting legacy? - Analysis

Mike Tyson has endorsed the fight as the biggest bout of the last 30 years

There are few fights that leave a lasting legacy on boxing. Muhammad Ali v Joe Frazier, Thomas Hearns v Marvin Hagler. In recent memory, Floyd Mayweather v Manny Pacquiao, Tyson Fury v Deontay Wilder.

Crawford and Spence hope this fight can occupy that elite list. Mike Tyson, the youngest heavyweight champion in history, believes this fight will hold a special place in history.

"I haven't seen things like this in over 30 years," Tyson said, before flipping the coin that gave Crawford the power to decide who walks first on Saturday evening.

Crawford has already been undisputed champion at light-welterweight; Spence is bidding to become the 10th male fighter in the four-belt era to claim an undisputed crown.

While neither man has engaged in much trash talk, there was a palpable energy between as they faced off for the first time in fight week. Crawford curled his lip as Spence broke eye contact first.

Both men may appear calm and composed, but the magnitude of their fight is not lost on them.

Their profiles can skyrocket with a fantastic fight, just as Wilder and Fury's did after their first encounter. Their careers could ultimately be defined by their next performance.

Can they deliver?