Gennady Golovkin beats Vanes Martirosyan, ties Bernard Hopkins’ defense record

CARSON, Calif. — The fight wasn’t the mega event unified middleweight world champion Gennady Golovkin expected to take part in, but that did not stop him from making boxing history Saturday night at StubHub Center.

Golovkin blew away last-minute substitute opponent Vanes Martirosyan with a devastating knockout in the second round to retain his title for a record 20th consecutive time to tie the all-time 160-pound division mark set by legend Bernard Hopkins in 2005.

Golovkin, boxing’s longest-reigning active world champion, was supposed to headline a major HBO PPV event in a rematch with Canelo Alvarez on Saturday at T-Mobile Arena in Las Vegas, but after Alvarez failed two Voluntary Anti-Doping Association-administered drug tests for the banned performance-enhancing drug clenbuterol in February, the fight was called off.

With or without Alvarez, GGG was determined to fight Saturday, and he took a massive pay cut — from a mid-eight-figure payday for the Alvarez sequel to $1 million — as promoter Tom Loeffler scrambled to make it happen. They settled on Martirosyan, a selection met by tremendous criticism because he was coming off a loss, he hadn’t fought in two years, and he was moving up in weight to face the most fearsome middleweight on the planet.

In fact, the IBF, which sanctions one of the belts GGG holds, viewed Martirosyan as such a weak opponent that it refused to approve the fight, so that belt was not at stake.

But Martirosyan was in shape, he was near weight, and he has a bit of a fan base in his hometown of nearby Glendale, California. Plus, he fit the budget to the tune of a $225,000 purse. Since desperate times call for desperate measures, Loeffler was able to quickly make a deal with Martirosyan promoter Don King, with the fight being…