Terence Crawford could be three victories away from doing something that has never been done in the four-belt era: standing as an undisputed champion in three weight classes.

Or the Nebraska fighter driven to defeat the most daunting opponent within his reach can pursue more glory and more riches than he has ever gathered by going after a showdown with undisputed super middleweight champion Canelo Alvarez.

“If he has the ability to unify at [junior middleweight], he’s going to retire as the best fighter who’s ever lived,” ProBox TV analyst Chris Algieri said on Tuesday’s episode of “Deep Waters.” “And I don’t think there’s any question about that.”

Of course, the 36-year-old Crawford (40-0, 31 KOs) could also be a three-division undisputed and five-division champion by defeating current WBA 154-pound champion Israil Madrimov in their currently scheduled Aug. 3 main event in Los Angeles and then moving up in weight again to meet Alvarez (61-2-2, 39 KOs).

Turki Alalshikh, chairman of Saudi Arabia’s General Entertainment Authority and funding source of the L.A. card, said in a recent interview that he is aiming to stage a Crawford-Alvarez fight, perhaps by the end of the year.

But “Deep Waters” analyst Paulie Malignaggi, a former welterweight titleholder, said that pressing for a Crawford bout instead of Alvarez versus unbeaten former super middleweight titleholder David Benavidez (28-0, 24 KOs) is a casual-fan move by Alalshikh and a “dangerous” option for Crawford.

“The amount of eyeballs that are going to be on [Canelo-Crawford] … the majority will be casuals who maybe watch one fight this year,” Malignaggi said.

“The fight that everybody wants to see within boxing circles … [is] Canelo-Benavidez.”

Veteran trainer Teddy Atlas said on “Deep Waters” that Alvarez will dictate who fights who because he’s “the golden goose that lays the golden eggs.

“I’m not going to knock the fight, because Crawford is that special,” Atlas said. “In the gym, it’s not unusual for a special fighter to be boxing and sparring with middleweights and light heavyweights … so when you really get down to brass tacks, [Alvarez-Crawford] is not that crazy.”

What makes it “crazy,” Atlas said, is the fact that Alvarez has options including Benavidez or a rematch with unbeaten light heavyweight champion Dmitry Bivol. Both could be on the table if the other light heavyweight champion, Artur Beterbiev, cannot return from his ruptured meniscus injury to fight Bivol in an undisputed light heavyweight title fight by year’s end.

Bivol defeated Alvarez by unanimous decision two years ago this month.

Algieri’s point is that, for recently undisputed 147-pound champion Crawford, meeting 168-pound champion Alvarez (should he take Madrimov’s 154-pound belt in August) is not a nothing-to-lose proposition.

“There’s always something to lose when you’re fighting a man three weight classes above you – [a champion] substantially bigger than you. You can always get hurt,” Algieri said.

Crawford staying at 154, should he defeat Madrimov – with Sebastian Fundora and Bakhram Murtazaliev as fellow champions – is the shrewder legacy move even if the caliber of champions improve with Aug. 3 card participants Tim Tszyu and Vergil Ortiz also so near a 154-pound title. 

“This guy [Crawford] is on a track to be the best fighter who’s ever lived – literally, pound-for-pound all time, if he stays undefeated,” Algieri said.

“If he goes up and loses to Canelo, that’s not part of the equation anymore.”

Algieri remains skeptical that Alvarez, because of their size difference, fiercely wants to fight Crawford.

“Canelo has alluded to the fact that he has nothing to gain,” Algieri said. “If he beats [Crawford], he’s supposed to – ‘I’m three weight classes above this guy. But if he beats me, I look like a fool.’

“So while Canelo feels he has everything to lose, for Crawford, it’s not everything to gain. It’s still a dangerous fight, and it’s a tough situation for his legacy.”