VIDEO Watch Gennady 'GGG' Golovkin's Brutal Knockout Win In Round 2

While boxing fans were denied a Cinco de Mayo rematch of Gennady "GGG" Golovkin vs. Canelo Alvarez, an announced attendance of 7,837 at StubHub Center in Carson, California, were at least treated to a convincing win by Golovkin over Alvarez's replacement.

Golovkin on Saturday night made quick work of substitute opponent Vanes Martirosyan with a second-round knockout to retain his WBA (Super), WBC, and IBO middleweight titles.

Martirosyan, an Armenia-born boxer who grew up in Los Angeles, came out aggressive in the opening round. The 32-year-old, who has fought against star boxers Jermell Charlo and Erislandy Lara, was able to land some solid punches.

"Vanes is a very good fighter," Golovkin said. "He caught me a few times in the first round."

But Golovkin took care of matters in the second, with a flurry of power punches that floored Martirosyan after 1 minute 53 seconds. Martirosyan said, "it was like being hit by a train."

It was typical Triple G, who has 34 knockouts in 39 fights. It was also a return to form for the 36-year-old, who had failed to knock out his last two opponents, Alvarez and Daniel Jacobs.

Gennady Golovkin vs. Vanes Martirosyan finish. Absolutely lovely combination from GGG. pic.twitter.com/xgZbmup1bM

— The Boxing Post (@theboxingp) May 6, 2018

Golovkin improved his record to 38-0-1 while Martirosyan dropped to 36-4-1. In the post-fight interview, Golovkin made sure to call out Alvarez.

"If [Alvarez is] ready, I'm ready at any time," Golovkin said. "I've been the champion for nine years. I have lots of belts. I want anyone to come and try to take my belts. I don't care who it is."

After their 2017 fight ended in a draw, Golovkin and Alvarez were slated to have a rematch on May 5 at T-Mobile Center in Las Vegas. The fight was canceled after Alvarez failed two drug tests for the banned performance-enhancing drug clenbuterol.