LAS VEGAS -- Heralded lightweight prospect Jose Ramirez, a 2012 U.S. Olympian, made his pro debut in style, wrecking Corey Siegwarth of Denver in a first-round knockout victory on Saturday night.
The bout appeared on the undercard of the fourth fight between Manny Pacquiao and Juan Manuel Marquez.
Ramirez, 20, of Avenal, Calif., went 145-11 in the amateur ranks, won 11 U.S. national titles and was highly sought after by promoters. He signed with Top Rank last month.
He did not disappoint, turning in a dynamic performance against an obviously overmatched Siegwarth. According to CompuBox, Ramirez outlanded Siegwarth 32-2 in the fight.
Ramirez (1-0, 1 KO) was all over Siegwarth (2-2, 1 KO) from the opening bell, battering him around the ring. He sank a left hook to Siegwarth's body to score a knockdown and then finished the fight a few moments later when he trapped Siegwarth in the corner and blasted away with both hands until referee Vic Drakulich stepped in to stop it at 2 minutes, 5 seconds.
"I saw the expression on his face, a lot of pain," Ramirez said of Siegwarth on the knockdown. "I knew this fight was mine."
The left hook from Ramirez was impressive. In fact, Freddie Roach, who worked as an assistant in Ramirez's corner with head trainer and co-manager Armando Mancinas, was reminded of another Olympian with a great left hook, one who went on to stardom as a pro.
"He looks like a young Oscar [De La Hoya]," Roach said.
Ramirez, with about 30 family members and friends at ringside, admitted he was a bit nervous in his first pro fight and first fight without headgear. But he was all smiles afterward.
"It felt good, it was a whole different experience," Ramirez said. "I was a little tense, but I felt strong in there. Hopefully, with my next fight, I'll be able to control my nerves a little bit better."
In other undercard bouts that weren't part of the HBO PPV telecast:
• Featherweight Dodie Boy Penalosa Jr. (10-0, 10 KOs) of the Philippines scored a massive second-round knockout of Jesus Lule Raya (6-5-1, 1 KO) of Fort Myers, Fla. Penalosa caught him with a clean right hook on the chin to knock him out. Referee Jay Nady didn't bother to count, immediately calling off the fight at 1 minute, 12 seconds.
• Featherweight Alexis Hernandez (3-1, 1 KOs) of Las Vegas knocked down Jazzma Hogue (2-4-1, 0 KOs) of Farmington, N.M., and stopped him at 2 minutes, 20 seconds when Nady called off the bout.
• In the first fight of the night, featherweight Ernie Sanchez (14-3, 5 KOs), who comes from Pacquiao's hometown -- General Santos City in the Philippines -- knocked down Coy Evans (10-1-1, 2 KOs) of Philadelphia in the third round and went on to win a clear decision, 78-73, 78-73, 72-74.