Lagos, of Mexico, took the bout on two days notice and had to fly in from Houston, where he had been training, to replace Gabriel Munoz, who failed a physical.

Viloria improved to 9-0 with six knockouts, but had never gone past the fifth round in any of his previous eight bouts.

Lagos ran throughout the fight at Cipriani’s and refused to mix it up with Viloria, who won a gold medal at the 1999 World Championship and was a member of the U.S. team in both the 1998 Goodwill Games and 2000 Olympics as he built up a 230-8 amateur record.

“Brian was frustrated with the guy’s style,” said trainer Fred Roach, after learning that his fighter had landed just 28 of 109 jabs. “We knew he was a runner and a mover, but we had to go on with the fight.

“The good thing is that we got a lot rounds out of this, but both of us would have preferred a better opponent and a tougher fight.”

Viloria said the fight was important — especially the win.

“This was a big moment for me — fight for a title — and I wanted to make a good showing,” Viloria said. “In a year or so, I want to move up.