Gennady Golovkin said his second-round knockout of Vanes Martirosyan wasn't intended to send a message to Canelo Alvarez.

Instead, it was the last-minute replacement for Alvarez who verbally tagged the Mexican superstar on Cinco de Mayo.

"I see why he's eating that kind of meat. I see why he's trying to get that extra edge," said Martirosyan, referencing Alvarez's failed drug test in March.

Golovkin won his 20th consecutive middleweight title defense by sending Martirosyan down at 1:53 of the second round on Saturday night.

Showing he has not lost any of his devastating power after his previous two fights ended in decisions, Golovkin (38-0-1, 34 KOs) tied Bernard Hopkins' record for middleweight title defenses with staggering fury.

After being tagged with a strong three-punch combination from Martirosyan (36-4-1) late in the first round, Golovkin responded with a devastating charge in the second. He started the eight-punch onslaught with a short left and pounced on the damaged Martirosyan, finally dropping him with two powerful lefts.

Martirosyan compared the sequence to being hit by a truck immediately after the fight, then likened Golovkin's punches to being hit by a train in the press conference.

"Every punch was the same power and that surprised me," Martirosyan said. "Thirty-six years old, and he's still fighting like that. He is the real deal."

The fight came together in hectic fashion after Golovkin's rematch with Alavarez fell apart. Golovkin and Alvarez fought to a draw last September and were set to meet again in Las Vegas on the Mexican holiday before Alvarez was suspended for six months by the Nevada Athletic Commission in April after testing positive for clenbuterol.

Alvarez has blamed the positive test on tainted Mexican beef, which led to Martirosyan's quip.

With the lucrative fight against Alvarez scuttled until this fall at the earliest, Golovkin was eventually able to put together a replacement bout in Southern California, where he built up a strong following with a series of title defenses at StubHub Center and the Forum. Despite short notice and a modest card, Golovkin drew a crowd of 7,837 and the biggest gate receipts for boxing at StubHub Center.

Golovkin made it worth their while, making an extended entrance by parading around the converted tennis court to the riff from the White Stripes' "Seven Nation Army."

The card also featured the first women's fight on HBO in the cable network's 45-year history of broadcasting boxing, as undisputed welterweight champion Cecilia Braekhus (33-0) remained undefeated with a unanimous decision over Kali Reis (13-7-1).

Braekhus won 97-92, 96-93 and 96-93 on the three scorecards despite being knocked down to one knee by a hard right from Reis in the seventh round. Reis nearly dropped Braekhus again in the eighth with another hard right, and the crowd booed when the result was announced after Reis' late charge.

UFC featherweight champion Cris Cyborg was in attendance and confirmed her interest in boxing against Braekhus, adding to a night where it was hard not to focus on the specter of fights that could have been and could still happen.

Focus on a rematch with Alvarez returned to the forefront immediately after Golovkin leveled Martirosyan.

Golovkin said after the fight he would take on all comers, including Alvarez. His attitude did not change in the subsequent press conference.

"Everybody want second fight, second step. Of course, I want to," Golovkin said. "It's very important for me and boxing people, for everything. Just I'm ready. Let's do it. September."

Besides his joke, Martirosyan had a prediction for how a second Golovkin-Alvarez fight might play out, especially if Alvarez feels the pressure to meet the demanding standards of Mexican boxing fans and go toe-to-toe with Golovkin after being responsible for the fight being scuttled in May.

"I think if Canelo stayed in front of Gennady, he would get knocked out cold," Martirosyan said.

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