By Keith Idec

Keith Thurman promised “someone is going to sleep” Saturday night in San Antonio.

Diego Chaves confidently predicted it’ll be Thurman that gets knocked out when the heavy-handed, undefeated welterweights square off for Chaves’ interim WBA welterweight title at AT&T Center. The Argentine champion considers Thurman untested and intends to prove Thurman’s movement has been more about smart matchmaking than anything.

“We know Thurman is very strong and he’s coming to fight,” Chaves said, “but I’m prepared for that. The strategy is no secret. Thurman is a strong kid and he’s going to come forward. I can’t let him come forward. I have to meet him in the center of the ring and land my punches.”

The 27-year-old Chaves has knocked out 82 percent of his professional opponents, but he has faced mostly modest opposition since he turned pro five years ago. The 24-year-old Thurman has an even higher knockout ratio (90 percent), but Chaves is eager to prove Thurman can’t withstand his power.

“My punches are strong and they’re going to hurt him,” Chaves said. “Nobody has ever hurt him before. I think my punches will and I’ll stop him before the 10th round. … My title stays with me and it’s going back to Argentina. I’m going to knock him out.”

Chaves (22-0, 18 KOs) hasn’t fought since Sept. 22, the night he stopped overmatched Panamanian journeyman Jose Miranda (12-13-3, 8 KOs) in the second round in Buenos Aires.

“I’ve had two opportunities with [former WBA welterweight champ] Paulie Malignaggi slip away and fall out, so it’s been a long time out of the ring,” Chaves said. “But I’m back in shape and ready to go.”

Thurman (20-0, 18 KOs, 1 NC), of Clearwater, Fla., has won twice since Chaves last competed. He sent Puerto Rican southpaw Carlos Quintana into retirement following a fourth-round stoppage of Quintana (29-4, 23 KOs) on Nov. 24 in Ontario, Calif., and unanimously out-pointed Slovenia’s Jan Zaveck (32-3, 18 KOs, 1 NC) in a 12-rounder March 9 in Brooklyn.

“I guarantee Saturday night you’re going to see a great performance,” Thurman said. “I’m a warrior for life. I prepare for death in every battle. I’m not scared of this. He’s 22-0, with 18 knockouts, and I’m 20-0, with 18 knockouts. That’s why I can guarantee you someone is going to sleep.”

The Chaves-Thurman match will be one of three fights Showtime will televise Saturday night, beginning at 9 p.m. ET/PT.

Former welterweight champion Andre Berto (28-2, 22 KOs), of Winter Haven, Fla., will battle Los Angeles-based Mexican Jesus Soto Karass (27-8-3, 17 KOs) in the 12-round main event. The third televised fight will pit Omar Figueroa (21-0-1, 17 KOs), of Weslaco, Texas, against Japanese southpaw Nihito Arakawa (24-2-1, 16 KOs) in another 12-rounder for the vacant WBC interim lightweight championship.

Keith Idec covers boxing for The Record and Herald News, of Woodland Park, N.J., and BoxingScene.com. He can be reached on Twitter @Idecboxing.