PHILADELPHIA, PA—Before he came out Saturday night, Jeison Rosario wore a quiet confidence in his dressing room. The junior middleweight is 24 from Santo Domingo, in the Dominican Republic, with two children, and one on the way.

He was facing an opponent in his hometown that no one gave him a chance against.

But Rosario also knew something.

He was better than anyone thought.

Before the weigh-in on Friday, Rosario promised he would shock the world—and on Saturday night at Temple University’s Liacouras Center he did, by pulling off an upset in stopping Julian “J-Rock” Williams at 1:37 of the fifth round to capture the WBA and IBF world junior middleweight titles.

Rosario (20-1-1, 14 knockouts) finished Williams by outlanding him 17-6 in Round 5 and 35-24 overall in power punches.

That started it.

Sensing Williams was in trouble, Rosario pursued J-Rock, who was shaky. Williams stumbled, but referee Benjy Esteves gratefully called it a slip, giving Williams some time to recover.

The extra time didn’t help.

Rosario continued his assault, landing a right and then a left hook, forcing Esteves to wisely step in and stop it at 1:37 of the fifth round.

“I’m so emotional in this moment right now,” Rosario said. “When I lost my last fight, I said I will never lose again until I become champion of the world and that’s what happened tonight. I came prepared. I knew before the fight that I was going to win it.

“I didn’t see my family and all I did was train. The main motivation are my children.”

Williams (27-2-1, 16 KOs) knew how dangerous Rosario could be.

“I wasn’t surprised he was so good,” Williams said. “I told everybody he’s a real fighter. I have to accept it. The cut blurred my vision a little bit but it wasn’t the reason why I lost. He was the better fighter tonight. We’ve got a rematch clause. I’ll see him again soon. I’ll be back.”

The partisan Philadelphia crowd wasn’t ready to accept the verdict–which was a quality stoppage. Water bottles and debris rained down on the canvas minutes after the fight was halted.

The co-feature was in a word—horrible.

For large segments of the 12-round junior lightweight interim title fight, neither Chris Colbert nor southpaw Jezreel Corrales seemed willing to engage until the final three rounds.

Sure, there were sporadic moments when there were brief exchanges. But there was nothing sustained until the 10th.

Colbert (14-0, 5 KOs) wound up winning a mostly boring 12-round unanimous decision over Corrales (23-4, 9 KOs).

“He was a great fighter,” Colbert said of Corrales. “People don’t realize that, because he had a bad decision against Ladarius Miller. But he’s a great fighter. He’s very awkward. He’s slick and fast. It was hard to catch him because he was running, but he came to fight. I take my hat off to him.

“I had confidence coming into the fight. I knew I was going to dominate the fight and I told you all that before the fight happened. He was running and I was trying to catch him, so I told my corner, let’s have a dog fight. We got 12 rounds. I’m in shape. You see, I didn’t sit down one round. I’m in shape and I came to fight. I wasn’t going to leave without this title.

“I’m not ducking nobody and not dodging nobody. I’m here to fight and I’m here to stay.”

Colbert won the first round on activity, and began the second round as a southpaw, before switching back to an orthodox stance. Most of the first two rounds were filled with feinting and fakes. Neither seemed too willing to engage.

Colbert started the third bouncing on his toes. Corrales remained stable, and did little. Colbert did a little more, and midway through the round, boos began raining down on the inactive fighters.

After three, Colbert appeared to be ahead, 2-1, though it was hard to figure, since both fighters looked unwilling to throw a punch.

At the outset of the fourth, Colbert began pumping the jab and finding his range. He used to jab to set up a solid right to the body. Near the end of the round, Corrales missed and was out of position, when Colbert grabbed him from behind and looked as if he was going to body slam the Panamanian. He wisely chose to put down Corrales.

In the fifth, Colbert landed a left to Corrales’ face. Then the round fell into the same feinting, faking rhythm as the previous four rounds. Colbert may have won the fifth based on the one looping left he landed early in the round.

After five, it was easy to see Colbert ahead, 4-1.

Midway through the sixth, Colbert nailed Corrales with a straight right to the face. Moments later, boos came down on the fighters again.

Corrales caught Colbert with a right in the seventh, perhaps the best connect he had in five rounds. Colbert, however, closed the seventh with a nice combination, forcing Corrales to retreat.

Feeling confident in the eighth, Colbert bounced a few punches off of Corrales’ head, and Corrales, waiting to counter, did nothing to retaliate. Colbert nailed Corrales with a right in the last minute of the round, popped the retreating Corrales with a left.

In the 10th, a Colbert left hook and a right on top of the head downed Corrales.

The 10th round broke up the monotony of the fight. A Colbert left hook, followed by a right on top of the head downed Corrales. It was then that it finally sunk into the Panamanian that he could be in trouble.

Corrales, a bubbling welt under his right eye, was swung almost out of the ring near the end of the 11th. There was some slight urgency on Corrales’ part in the last round, but he couldn’t maintain anything, and Colbert tied him each time the fighters got close.

In the end, judges Steve Weisfeld and Dewey LaRosa saw it 117-110, and David Braslow had it 116-111—all for Colbert.

“I did my job in there,” Corrales said. “My strategy was to hit and not get hit. I felt like I made him struggle for a lot of the fight. The knockdown wasn’t from being hurt; it was my balance. Our feet got tangled and I lost my balance.

“I came in here to win. We both did our jobs, but the judges scored his pushing more than his punching.”

Junior middleweight prospect Joey Spencer (10-0, 7 KOs) landed a few punches and beanpole southpaw Erik Spring (13-4-2, 1 KO) landed less, giving Spencer a six-round unanimous victory. The only action in the fight came in the last five seconds, when Spencer popped Spring in the face with a left to the chin.

The judges didn’t have too much guess work to come up with identical 60-54 scores.

“I was in there with a cagey, long southpaw,” Spencer said. “And to be honest, when a guy is fighting as cagey as he was, it’s really hard for a guy with my style to just pull something out of nothing. He was a real defensive guy.

“At the end I really just pressed him, said I’m going to finish strong, and hit him with some good shots and if I had done that in the first or second round, I would have ended it early.

“I’m glad to get the six rounds in. Experience is everything. You’re only as good as your next fight. I’m happy to get in there and get some good experience and I did my thing and got the shutout.”

On the untelevised undercard, bantamweight Miguel Angel Román, Jr. made his pro debut with a four-round decision over Antonio Lucaine (0-3). Heavyweight Norman Neely (5-0, 5 KOs) stopped Larry Knight (4-23-1, 1 KO) at 1:21 in the first round of a scheduled four-rounder.

Philadelphia junior middleweight Paul Kroll (7-0, 6 KOs) scored a fourth-round TKO over Marcel Rivers (7-3, 4 KOs) at :49 in a scheduled eight-rounder. Middleweight Kyrone Davis (15-2, 6 KOs) stopped Antonio Todd (7-3, 4 KOs) at 2:28 of the fourth in a scheduled eight-rounder.

Super bantamweight Romuel Cruz (4-0-1, 2 KOs) won by first-round knockout over Julio García (3-4, 2 KOs) at 2:56 in a scheduled four-rounder.

Vito Mielnicki Jr. (4-0, 3 KOs) looked good in beating Preston Wilson (6-4-1, 4 KOs) by four-round decision. It marked the first time Mielnicki Jr., the budding 17-year-old welterweight prospect, went the distance for the first time.

Junior middleweight southpaw Jorge Cota (30-4, 27 KOs) plowed through the gangly Thomas LaManna (28-3-1, 10 KOs) and stopped him in the fifth round of a scheduled 10-rounder. From the outset, Cota suffocated the taller LaManna, pelting him inside with uppercuts.

At 1:22 of Round 5, LaManna’s corner correctly threw in the towel.

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