Manchester's John Murray has accepted Amir Khan's challenge to his British lightweight rivals to "fight me now before it's too late".
Murray has won all 20 of his professional fights
Khan, 20, has his 12th pro fight against Steffy Bull in Cardiff on Saturday, but believes he will soon be fighting at world level.
"I noticed Khan didn't mention my name," said the WBC Youth champion, who makes his Las Vegas debut on 5 May.
"I'll fight him, no problem. Stop talking rubbish - put up or shut up."
Khan wants to fight in Vegas, so why not fight me on 5 May? I would mow him down inside the distance
Khan called out former British champion Graham Earl and current Commonwealth super featherweight king Kevin Mitchell on Tuesday and said he wanted to be a world champion "this time next year".
Murray, 22, called Khan's claims "insulting" and even offered to defend his WBC belt against him in Vegas, where he will appear on the undercard of the Oscar de la Hoya-Floyd Mayweather super-fight.
"It's an insult to fighters proven at championship level to start saying that they need to fight you before you move on to bigger things," said Murray, who was voted young fighter of the year by British boxing writers in 2006.
"But he doesn't say he wants to fight me because he knows, out of everyone coming through, I'm the best.
"He knows it would be too much of a risk. But we're both from the North West and it would be a massive fight there.
"And I've heard he wants to fight in Vegas, so why not fight me on 5 May? I would mow him down inside the distance."