Unheralded junior welterweight contender Jason Welborn fought like anything but a stay-busy opponent by routinely backing Jarrett Hurd up to the ropes with power shots. Then the unified 154-pound champion woke up.

Hurd (23-0, 16 KOs), in his first bout back from shoulder surgery, appeared so unbothered early by Welborn's power that he allowed him too much leeway in closing distance in an effort to get in some rounds. But once the native of England began to have to much success, Hurd jolted forward with a vicious right uppercut to the chest that finished him in Round 4.

In the co-main event of Saturday's Deontay Wilder-Tyson Fury pay-per-view card, the 28-year-old Hurd defended his WBA and IBF titles in his first bout since a breakthrough April victory over longtime titleholder Erislandy Lara by split decision in one of 2018's best fights.

"I'm just coming of surgery so I wanted to see how I worked off the jab. I felt good I was working behind the jab," Hurd said. "I got caught on the ropes and got caught with some shots and said 'that's enough. He got enough TV time.'

"I heard the crowd and I didn't want to get brave. So I turned it up and got the knockdown.

The victory appeared to set Hurd up for a second unification fight against Jermell Charlo (31-0, 15 KOs), provided the WBC champion gets past Tony Harrison on Dec. 22. Charlo entered the ring to trade trash talk with Hurd after the fight until both needed to be separated.

"We definitely want Charlo. I'm calling the shots. I'm number one right now. When I say answer the phone, answer the phone. I got the date.

"I'm going to have a hometown fight. I'm coming off two fights with southpaws so I want to fight a right hander and then I want the Charlo fight."

Hurd's performance was far from stellar as he didn't use his jab enough and regularly allowed Welborn (24-7, 7 KOs) to crowd him. Eventually, Hurd paid a price as Welborn exploded with a barrage of clean hooks to close Round 3 that forced Hurd to cover up in the corner after getting his so clean.

The next round opened the same way as Welborn pushed Hurd back and began to unload sensing he had an opening to score a massive upset. He appeared to hurt Hurd once more before the sequence triggered a change in Hurd's demeanor. He walked Welborn down with power shots before finishing him to the body.

Welborn appeared to be fine and possibly mistimed his rise at the count of 10 which forced referee Dr. Lou Moret to count him out in an awkward finish.

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