LAS VEGAS — Reito Tsutsumi’s impressive start to his promising career continued Saturday at Allegiant Stadium.

The 23-year-old Japanese junior lightweight prospect stopped Javier Martinez in the first round of a scheduled six-rounder on the Canelo Alvarez-Terence Crawford undercard at Allegiant Stadium. Tsutsumi (3-0, 2 KOs) dropped Martinez barely two minutes into their bout.

Martinez (7-3, 4 KOs) reached his feet, but referee Allen Huggins didn’t let him continue because he didn’t adequately respond to his commands. The official time of the stoppage was 2:18.

“I was kind of watching him for a little while,” Tsutsumi told The Ring’s Max Kellerman after his win. “It took me a while to figure his moves out. I [went to the] body and I slowly but surely figured [out] his moves. And now it was my day.”

Tsutsumi and Martinez traded hard punches during the middle minute of the first, until the former's power proved too much. He landed thudding shots to Martinez’s body and head before two left hands up top knocked him flat on his back.

Tsutsumi recorded his second straight knockout. He stopped overmatched Michael Ruiz (2-8-1) in the second round of his previous appearance July 12 in New York on the Ring III card headlined by Hamzah Sheeraz and Edgar Berlanga.

Dallas’ Martinez at least has a winning record, albeit against a low level of opposition.