Timothy Bradley could face Britain's Amir Khan in a fight to unify the light-welterweight division after beating Devon Alexander in Michigan.
Bradley, the WBO champion, defeated WBC holder Alexander on points after the 12-round contest was stopped in the 10th following an accidental headbutt.
The previously undefeated Alexander, who was unable to continue, said: "I couldn't see. He's got a tough head."
Bradley confirmed: "Khan is probably number one on the list."
Bolton fighter Khan, who holds the WBA belt, announced after wrapping up a unanimous points victory over Marcos Maidana in December that he wanted to unify the division, talking up a fight with the winner of Bradley v Alexander.
And the 24-year-old is now likely to get his wish and face Bradley, who was ahead 98-93, 97-93 and 96-95 on the cards when the bout was halted.
The first highly anticipated fight of 2011 failed to explode into life, with southpaw Alexander attempting to control the contest from a distance with his jab while the shorter Bradley stalked the ring landing occasional rights.
A Bradley right rocked Alexander in the third round, as did several others in the ninth, but Bradley's substantial lead was largely down to occasional flurries.
And ultimately it was Bradley's head that did most damage. The two men clashed heads in the third and again in the 10th, both ruled accidental by referee Frank Garza, who felt it necessary for Alexander to return to his corner on the second occasion.
The doctor was then called over and he called a halt to proceedings after ruling that Alexander could not keep his left eye open.
Unbeaten Bradley, who has recorded 11 knockout victories in his 27 wins, refused to apologise for leading with his head, and said: "I'm ruthless. I'm reckless.
"If that's the best in the world, that's weak. I did not want the fight to end that way. I really wanted to finish the fight."
The 27-year-old then turned his thoughts to his next challenge, with Philippine sensation Manny Pacquiao and fellow American Floyd Mayweather Jr also on his radar.
"I would love a chance with Floyd Mayweather," Bradley said. "I think I've got to take Amir Khan out next, then there will be no doubt who the best 140-pounder is in the world.
"But the key name on the list down the road is Manny Pacquiao."