OXON HILL, Md. -- Previously undefeated Maxim Dadashev was taken to a hospital following his 11th-round loss to Subriel Matias on Friday night and was undergoing surgery because of brain swelling, a source told ESPN's Bernardo Osuna.

After trainer Buddy McGirt threw in the towel after Round 11 of the IBF 140-pound eliminator, Dadashev needed assistance leaving the ring and vomited.

He left the arena on a stretcher and was taken to UM Prince George's Hospital Center.

"I think right now he's dehydrated -- I think he really needs some IVs in him,'' McGirt said after the fight. "He didn't want to drink much water in the corner -- he kept spitting it out. He had one hell of a fight, tough fight. He took a lot of shots. I think it was time to stop it."

Throughout the bout, Matias, 27, of Fajardo, Puerto Rico, steadily came forward, throwing hard shots with both hands.

Dadashev, 28, of Saint Petersburg, Russia, spent much of this fight on his back foot, circling the ring. And while Matias was the constant aggressor and able to control the tempo and pace of the bout, Dadashev was never willing to stand and trade with him.

According to Compubox, Matias outlanded Dadashev 319-157; 112 of Matias' punches were body shots.

As the rounds mounted, Matias steadily piled them up in his favor, outworking Dadashev and pounding the body consistently. In the later rounds, either because of exhaustion or desperation, Dadashev began to sit inside the pocket and fight with Matias. But while he had some success, he was overwhelmed by Matias, whose punches had more effect.

The scores at the time of the stoppage in favor of Matias were 109-100, 108-101 and 107-102.

"First of all, I'm very grateful for this opportunity. I showed that I am not just a power puncher. I also can box. I was dominating the fight. I focused my offense on going to the body, and that's how I stopped him from running,'' Matias said.

But his fallen foe also was on his mind.

"I hope that Maxim is all right. He is a great fighter and a warrior."