Errol Spence Jr.’s next fight won’t come against Terence Crawford, and it won’t even take place for Spence’s three welterweight titles.

Instead, Spence will meet Keith Thurman in a junior middleweight bout that’s expected to take place in April, sources told ESPN. A matchup between Spence and Thurman was highly sought after years ago when both boxers were at the top of the welterweight division with three titles between them.

After Spence won his first title from Kell Brook via 11th-round KO in May 2017, fans were clamoring for a unification bout with Thurman, but the latter showed no interest. Instead, Thurman didn’t fight for the remainder of 2017 nor in 2018 as he battled injuries to his hands and elbows.

Thurman returned in January 2019 with a tougher-than-expected win over Josesito Lopez before he dropped a split decision to Manny Pacquiao that July. Thurman, 34, has competed only once since, a February decision victory over Mario Barrios.

During that time, Spence established himself as one of the two best welterweights in the world (alongside Crawford) and one of the best boxers in the game. He’s currently rated No. 4 pound-for-pound by ESPN.

He returned from a serious car crash that hospitalized him in October 2019 to defeat Danny Garcia. Spence was then set to fight Pacquiao in August 2020 before he required surgery to repair a detached retina.

Spence returned again in April and scored a 10th-round TKO of Yordenis Ugas to add a third welterweight title. He entered negotiations for a highly anticipated undisputed welterweight championship fight against Crawford, but those extended talks failed to deliver a deal.

Now that Spence is moving up to 154 pounds, it’s unclear if we’ll ever see him and Crawford fight. What must take place for that fight to finally materialize? And how do Spence and Thurman match up? An early look at Spence-Thurman:

Will Spence fight at 147 again?

Spence will surely want to see how he feels at 154 pounds before he makes any decision. But typically, when fighters move up in weight, they don’t return unless it’s for a mega fight. And Spence has long been large for the 147-pound weight class. Now at 32, it’s surely becoming more difficult to make weight.

Spence competed at 152 pounds in the 2012 Olympics but has fought at 154 pounds (or above) just once, when he weighed 156.5 for a 2015 victory over Chris van Heerden. That was before Spence defeated Brook to win his first world title, and he’s since fought 10 consecutive fights at 147 pounds, including six consecutive title defenses.

He’s long said that he would eventually move up to 154 pounds, but the division lacks top-tier talent outside of Jermell Charlo, who’s the undisputed champion at junior middleweight. Spence and Charlo are both trained by Derrick James in Dallas, so it wouldn’t be a surprise if Spence has no interest in fighting his training mate.

Besides Charlo, fights against Brian Castano and Sebastian Fundora are highly intriguing, but the division still doesn’t come close to matching welterweight in terms of talent.

Can Thurman pull off the upset?

Thurman is undoubtedly an elite talent, but inactivity and a rash of injuries leave questions about his current form.

Thurman has competed only once since a thrilling fight with Pacquiao in 2019 that he lost via split decision. That only fight came in February, a unanimous-decision win over Barrios. Thurman looked like his usual self during the first half of the bout but faded a bit down the stretch.

Still, it was his first fight in 31 months so he’ll surely be in better form against Spence. When Thurman was at his best, he was one of the top pound-for-pound boxers in the sport. In wins over Garcia and Shawn Porter during his lengthy title reign, Thurman showed off his excellent jab, ability to control range and also his vaunted power.

If Thurman can rediscover his form, he should be able to trouble Spence with his jab and precision punching much like he did during the second half of the fight against Pacquiao. But if Thurman is past his best days following all the inactivity and surgeries to his hands and elbows, Spence should earn a comfortable points win in his junior middleweight debut.

Will the Crawford fight ever happen?

Crawford was in talks to fight Spence last year, but when those negotiations stalled, Crawford turned to a December bout with David Avanesyan, which he won via sixth-round KO.

Still, Crawford was available to fight in the spring, but now Spence has an opponent lined up. If Spence-Thurman takes place in April as expected — rather than, say, May or June — that would leave the fall for a bout between Spence and Crawford.

Complicating matters now: the weight. Crawford won his first title at 135 pounds and went on to win the undisputed championship at 140 and is currently a 147-pound champion. Crawford expressed interest in a fight against Jermell Charlo for the undisputed 154-pound championship, but the weight still provides another stumbling block.

Even if Crawford and Spence could agree to a deal for a fight at 154, it removes some of the shine from the fight. Crawford and Spence are two of the five best boxers in the world regardless of weight, but a big reason why this matchup is so anticipated is because it’s for the undisputed championship between the unquestioned two best 147-pounders in the world.

Of course, Spence could always decide to return to 147 pounds for a fight with Crawford, but that remains to be seen. WBA president Gilberto Mendoza told ESPN that Spence will have 60 days after the Thurman fight to close a deal for a bout with Crawford or will instead be ordered to defend his title against the winner of Vergil Ortiz Jr.-Eimantas Stanionis. Spence could also elect to campaign at 154 and relinquish his 147-pound titles.