LAS VEGAS — Former light heavyweight world title challenger Isaac Chilemba was trying to bounce back from two losses in a row to remain relevant in the division, while Oleksandr Gvozdyk, a 2012 Olympic bronze medalist, was trying to brandish his credentials as a rising contender.

It was Gvozdyk who accomplished his goal, forcing Chilemba to retire on his stool after the eighth round with a right elbow injury Saturday night on the Sergey Kovalev-Andre Ward undercard at T-Mobile Arena.

“Left jab, left hook and straight rights to the body really hurt him,” Gvozdyk said. “People don’t think I have a lot of fights, but I had over 250 amateur fights. I just broke him down.”

Gvozdyk (12-0, 10 KOs), trained by Robert Garcia, is close friends with Olympic teammate and junior lightweight world titleholder Vasyl Lomachenko, who was ringside. Gvozdyk appeared on his way to a victory even before Chilemba’s injury. The Ukrainian fighter was steadily breaking down the slower, smaller Chilemba with precise punches and pesky jabs to the face.

Gvozdyk had Chilemba (24-3-2, 10 KOs) in deep trouble in the fourth round, forcing him to the ropes and unloading a sustained flurry that had referee Jay Nady looking closely.

“A new star was born tonight,” said matchmaker Brad “Abdul” Goodman of Top Rank, which promotes Gvozdyk.

Chilemba, 29, a native of Malawi who fights out of South Africa, was working with Roy Jones Jr. as his trainer for the first time, but the pairing did not seem to stoke much fire in Chilemba.

“I am devastated,” Chilemba said. “If I hadn’t hurt my right arm in the third round, it would have been a completely different outcome. I was in an incredible amount of pain from the third round through the rest of the fight.”

Chilemba was coming off a decision loss to Kovalev in a July world title fight.

Perez-Hooker a draw

Junior welterweight Maurice “Mighty Mo” Hooker predicted he would knock out former lightweight world titleholder Darleys Perez, but did not stop him. Instead, Hooker came away with a shocking draw in a fight Perez appeared to clearly win.

One judge had it 97-93 for Perez, one had it 97-93 for Hooker and one had it 95-95.

Perez, 33, of Colombia, lost his lightweight world title in November 2015 by fifth-round body-shot knockout in a rematch of a draw with Anthony Crolla. Perez won his next fight and then moved up in weight to face Hooker, a 27-year-old prospect from Dallas for whom promoter Roc Nation Sports had high hopes.

But Perez (33-2-2, 21 KOs) seemingly upended those expectations by befuddling Hooker, a friend and sparring partner of unified junior welterweight champion Terence Crawford.

Perez, who wobbled Hooker (21-0-3, 16 KOs) with a left hand in the ninth round, came forward throughout the fight and let his hands go while Hooker backed up constantly and rarely landed anything solid.

Stevens wins decision against De La Rosa

Middleweight Curtis Stevens (29-5, 21 KOs) won a unanimous decision against James De La Rosa (23-5, 13 KOs) in a fight that began with a lot of action and then slowed to a crawl. Stevens won 98-90, 96-92 and 96-92.

“I give myself a C-minus. Could have thrown my jab a little more,” Stevens said. “I am glad I got the W but I am a little disappointed in myself. The jab was good, but I could have popped that s— a little more. Hurt my left hand in the fourth round. He’s got a hard-ass head. But I am glad I got the win.”

Stevens, 31, a powerful puncher from Brooklyn, New York, took control right away and dropped De La Rosa with a left hand behind the ear with 20 seconds left in the opening round. Things did not get any better for De La Rosa, 29, in the second round as Stevens opened a cut over his left eye.

They engaged in a ferocious exchange in the third round in which both landed clean shots, and De La Rosa’s left eye began to swell.

Stevens appeared to have De La Rosa in trouble in those early rounds but could not finish him, and then the pace slowed down and the fight meandered on. De La Rosa, of Harlingen, Texas, appeared to have some good moments in the later part of the fight as Stevens began to tire, but could not put any punches together to do any damage.

Referee Russell Mora docked Stevens one point for a low blow in the eighth round.

Stevens, who lost a world title challenge by eighth-round knockout to Gennady Golovkin in 2013, won his second fight of the year and, coincidentally, both were at T-Mobile Arena; he knocked out Patrick Teixeira in the second round in May on the Canelo Alvarez-Amir Khan card, the first boxing event to be held at the new arena.

De La Rosa lost his third fight in a row.

“I don’t have any comments,” De La Rosa said. “People saw what it was.”

• Darmani Rock (5-0, 4 KOs), a 20-year-old heavyweight prospect from Philadelphia, rolled to a nondescript decision win against Brice Ritani-Coe (4-5-1, 3 KOs), 30, of Las Vegas. The 6-foot-4, 247-pound Rock, who won the 2015 National Golden Gloves and U.S. National Amateur titles, won 40-36, 40-36 and 39-35.
• Toledo, Ohio, featherweight Tyler McCreary (12-0, 6 KOs), 23, won an unpopular majority decision against Vincent Jennings (5-3-1, 4 KOs), 32, of Grand Rapids, Michigan. Jennings lost his third fight in a row, but as far as the crowd was concerned he won the fight, which featured very little action; boos rained down when the scores were announced, 59-55 and 58-56 for McCreary and 57-57.

  “It was a tough fight,” McCreary said. “Jennings is crafty for his size. He’s powerful too. But I know I took him every round. I had height and speed all to my advantage. I’m pleased with my performance. I dug deep. It was a great learning experience. Next time, I will be more prepared.”

• Junior welterweight prospect Sonny Fredrickson (15-0, 9 KOs), 22, of Toledo, Ohio, outfought Gabriel Deluc (11-2, 2 KOs), 26, of Boston, in a competitive and entertaining eight-rounder. Fredrickson, who put together a lot of solid combinations and was on the attack for most of the fight, got the nod 78-74, 78-74 and 77-75.

  “It was a hard, tough fight,” Fredrickson said. “I think I took the edge during the middle rounds. But I also had a strong beginning and finished strong at the end. It was a good fight and a tough opponent that will allow me to grow and build.”

• Middleweight Bakhram Murtazaliev (7-0, 5 KOs), 33, of Russia, blasted Uzbekistan native Botirsher Obidov (6-1-1, 2 KOs), 24, who is based in Kissimmee, Florida, via a second-round KO. Murtazaliev was ruthless, dropping Obidov hard three times in the second round, including a powerful right hand on the chin that sent him to the mat as referee Vic Drakulich waved off the fight without a count at 2 minutes, 52 seconds.

• Middleweight Meiirim Nursultanov (1-0, 0 KOs), a 23-year-old Kazakhstan native fighting out of Oxnard, California, made his professional debut and laid a beating on Henry Beckford (4-6, 1 KO), 21, of Coram, New York, in a shutout decision win. Nursultanov attacked Beckford with right hands constantly and won 60-54 on all three scorecards.