Tom Loeffler, promoter for IBO, WBC, WBA middleweight champion Gennady Golovkin, feels very strongly that his fighter's upcoming rematch with Saul "Canelo" Alvarez is the biggest fight in the sport.

Last week, the two sides finalized a deal to stage the rematch on September 15th at the T-Mobile Arena in Las Vegas.

Another major fight in the works - is the heavyweight unification between undefeated punchers Deontay Wilder and Anthony Joshua - with the WBA, WBC, WBO, IBO, IBF world titles at stake.

While some would argue that Joshua-Wilder is the biggest fight in the sport - Loeffler disagrees, and he explains why the Canelo-Golovkin rematch is sitting in the top seat.

"Well, I think the bigger fight is the one that's actually happening. We've announced it for September 15th, Mexican Independence Day," Loeffler told SiriusXM Boxing.

"When you look at the fanbase that Canelo brings to the table, he's a proven pay-per-view star, sells out a lot of tickets. Triple G brings his fanbase, he sold out Madison Square Garden in New York, he sold out the O2 Arena in London, he sold out the Forum in Los Angeles, the Stubhub in LA, the T-Mobile in Las Vegas. So when you put those two fanbases together, I would have to go with Triple G and Canelo [as the bigger fight] just because of the international flavor of that fight and the strong fanbases that both guys bring to the table.

"When you have a heavyweight championship fight, with working with the Klitschko brothers for so long and doing so many championship fights, whenever you do a heavyweight championship fights it brings a little bit of extra flare - but these guys [Canelo and Golovkin] .. it really feels like the biggest fight in the sport of boxing right now... especially since its really happening on September 15."