LAS VEGAS – There were points during the weeks leading up to Shakur Stevenson’s fight with Edwin De Los Santos when his primary promoter thought Stevenson’s “various ailments” would cause him to withdraw from it.

Stevenson instead did what countless fighters before him have done by boxing through those injuries. Stevenson wouldn’t address speculation following his dull, unanimous-decision defeat of De Los Santos regarding a pre-existing injury to his left hand.

Bob Arum informed BoxingScene.com that Stevenson suffered a shoulder injury, among other injuries, during training camp for their 12-round, 135-pound title fight Thursday night at T-Mobile Arena. All three judges – Tim Cheatham (116-112), David Sutherland (115-113) and Steve Weisfeld (116-112) – scored their boring bout for Stevenson, but the three-division champion himself admitted afterward that it was “a bad performance.”

“I think that Shakur had to fight the fight he did because I think he had some injuries, that kinda thing,” Arum told BoxingScene.com on Friday. “I mean, I know we had him visiting doctors in the weeks before the fight for various ailments. So, I think he therefore fought a very cautious fight. But it was a stinker. It was a snoozer, and particularly after the fight before [a 12-round majority draw between Emanuel Navarrete and Robson Conceicao], which was one of the best fights of the year.”

Arum added that he was “absolutely” concerned that Stevenson’s injuries could’ve caused him to withdraw from a main event ESPN televised.

“I didn’t know specifically [what was wrong with Stevenson] because I was out of town,” Arum said. “But [Top Rank’s] Dena [duBoef, Arum’s stepdaughter] reported to me that he went to see this doctor and that doctor for various ailments about two or three weeks leading up to the fight. So, I was quite aware of that. It was a shoulder problem that he had. I don’t know specifically, but that’s what I was told not last night, but during the time that it was happening.”

The left-handed Stevenson told ESPN’s Bernardo Osuna during his post-fight interview in the ring that he “wasn’t feeling too good” prior to the start of his 12-round fight with De Los Santos for the then-vacant WBC lightweight title. Stevenson wouldn’t elaborate when Osuna pressed him for more information.

Stevenson (21-0, 10 KOs) also alluded to overtraining when he met with a group of reporters following his unimpressive victory over the Dominican Republic’s De Los Santos (16-2, 14 KOs). The 2016 Olympic silver medalist mentioned taking two months off from any sort of training to allow his body to rest because he returned to the gym soon after his sixth-round stoppage of Japan’s Shuichiro Yoshino on April 8 at Prudential Center in Stevenson’s hometown of Newark, New Jersey.

The 91-year-old Arum hopes Stevenson learned an invaluable lesson from training so hard, for so long, during the buildup toward his fight with De Los Santos.

“He’s a very competitive kid,” Arum said. “And so, he doesn’t train like a real seasoned pro would, just to accomplish certain things working up to the fight. He makes every training session a battle. You know what I mean? You can’t do that. I think that’s a bad lesson he learned from [Terence] Crawford. I think Crawford, when he spars, you know, he’s an older fighter, but Crawford is a tremendous competitor and when he spars he lets it all hang out.”

Arum acknowledged that Stevenson’s subpar performance Thursday night stunted the momentum that the three-division champion had built by beating Jamel Herring, Oscar Valdez, Conceicao and Yoshino impressively in his previous four fights. The Hall-of-Fame promoter doesn’t think, though, that this forgettable fight will hurt the 26-year-old Stevenson’s reputation if he can perform much better in his first fight of 2024.

“You’re judged by your last fight,” Arum said, “but he’s a young guy and, you know, if in his next performance, which I expect will be a scintillating performance, people will forget last night. If he was reaching the end of his career, I think people would say, ‘Whoa! Maybe he doesn’t have it anymore,’ that kind of thing. But he’s not. He’s a young guy and, you know, he’s just beginning to reach his potential.”

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.