The boxing match between Canelo Alvarez and Gennady Golovkin is considered to be the best fight of 2017 for a number of reasons. Near the top of the list is the unpredictable nature of Saturday’s bout at T-Mobile Arena in Las Vegas, which will determine the best middleweight in the world.

That unpredictability is reflected in the latest betting odds, which have Golovkin favored by the slimmest or margins. The undefeated 160-pounder has -155 odds to maintain his perfect record, via OddsShark, while Alvarez is just a +125 underdog.

It’s an unfamiliar position for both fighters, who are used to playing the role of the heavy favorite.

Golovkin hasn’t approached odds like this since becoming the face of the middleweight division. During his string of 23 straight knockouts, he routinely had -2000 odds or better. The 35-year-old hasn’t been quite as heavily favored as his competition has gotten better, but he was still a -480 favorite in his last title defense against Daniel Jacobs.

Alvarez was a decided underdog four years ago when he faced Floyd Mayweather. He’s been favored in every fight since, with oddsmakers giving him better than -400 odds in each of his last three bouts.

The aggressive styles of both fighters could make Saturday’s fight a war from start to finish. Neither boxer has ever been knocked down, but that could change as they feel one another’s power.

“We wanted to wait for Canelo to fill into the middleweight division because the very first fight that he wanted in the middleweight division was against the best, and that’s Gennady Golovkin. So it’s not gonna be an easy task for him. It’s gonna be a tough fight,” Oscar De La Hoya told International Business Times. “And I’m calling it, as long as it lasts, I think it’s gonna last maybe nine, 10 rounds, but it’s gonna be hell. It’s gonna be hell for both guys. It’s gonna be a good fight.”

The odds actually favor the fight to go the distance. Bovada.lv has set the line for the bout lasting 12 rounds at -140, while the odds are even for the bout to end with a knockout by either fighter.

Don’t tell that to Alvarez, who plans on sending Golovkin to the canvas.

“That’s what I want; I want to make it clear that I’m better than him,” Alvarez told a roomful of reporters at Madison Square Garden earlier this summer. “I want to make it very clear–no controversy, nothing–I’m better than him and there’s no need for another fight.”

Moving above the light middleweight class for the first time, Alvarez was unable to score a knockout in his last fight, though he defeated Julio Cesar Chavez Jr. in every round of their 164-pound bout. Only 15 of his 49 victories have come by decision, and he has four knockouts in his last seven fights.

When Golovkin went the distance with Jacobs six months ago, it was the first time that he didn’t score a knockout in nine years. Only two of his last 16 fights have lasted beyond the eighth round.

Canelo Alvarez Gennady Golovkin The betting odds for the fight between Canelo Alvarez and Gennady Golovkin don't favor a knockout. Pictured: Alvarez and Golovkin attend the Canelo Alvarez and Gennady Golovkin Press Tour at The Theater at Madison Square Garden on June 20, 2017 in New York City. Photo: Getty Images