Gennady Golovkin wastes little time in beating Marco Antonio Rubio

Rising star Gennady Golovkin, the baby-faced assassin from Kazakhstan, continued his tour to boxing super-stardom Saturday night at StubHub Center.

Golovkin is the middleweight champion of the world and his opponent, probably showing a decent degree of intelligence, lasted for one round and 1 minute 19 seconds of another. Marco Antonio Rubio of Mexico took a huge uppercut, then a left-handed overhand shot. He went down, appeared to consider getting up and then appeared to say, ah, the heck with it.

He did get up just before the 10-count ended, but the referee waved him out.

Rubio, who lost any title aspirations Friday when he weighed in at 161.8 pounds, or 1.68 over the limit, said Saturday that “he’s a great champion. He hit me hard, but not the hardest I’ve been hit. I got up, but the referee decided to stop it.”

It might have been the first time that a referee, in this case Jack Reiss, stopped a fight based more on perceived lack of interest by the downed fighter than on degree of injury.

Golovkin is 32 and his rise to popularity in the United States has only been stalled by his lack of fights in the country. He is 31-0, with 28 of those victories coming by knockout. The last 18 times he has stepped into the ring, he has knocked out his opponent.

Now, he has a plan to showcase his skills in the lucrative U.S. market. His first effort west of the Mississippi drew a sold-out 9,323.

After the fight, he thanked his California fans and called Los Angeles his home. That’s only slightly premature. He plans to buy a home here, his first choice is the Santa Monica area. He and his wife and 5-year-old son would spend the bulk of their time here, as well as some in their current residence in Germany.

“My son starts school next year,” Golovkin said. “I want him here.”

This victory, as light as it was on the competitive side, set up Golovkin perfectly for his first huge fight and huge payday. That would likely come in late spring or summer. He will fight once before that, probably in February in Europe.

The U.S. biggie after that could pit him against Miguel Cotto or Saul “Canelo” Alvarez. Golovkin’s victory over Rubio positioned him as a mandatory opponent after the expected Cotto-Alvarez match in May.

Pressed immediately afterward for indications of his future, Golovkin said what he always does. Only unlike most boxers, he means it.

“I will fight anybody,” Golovkin said.

He entered the ring to chants of “Triple G,” his nickname. He was clearly the fan favorite, even though he was fighting a Mexican in L.A. He was also clearly the subject of fan curiosity, which is exactly what his promoters, K2, wanted.

Right now, like the venue in which he fought Saturday night, there appears to be no ceiling to Golovkin’s future.

Just in case Golovkin and Rubio didn’t provide enough excitement in the main event, the semi-main between Nonito Donaire and Nicholas Walters had plenty.

Donaire, a veteran from the Philippines and as popular a boxer as there is today, took an overhand right to the back of his head in the last second of the sixth round and was finished.

Donaire, already down once in the third round, tried to get up this time, but wobbled and was called out by the referee when he started to collapse against the ropes.

These were featherweights — a World Boxing Assn. super-featherweight title match — who fought like 160-pounders.

Afterward, it was a surprising love-in.

Donaire, who is 31 and been fighting pro fights since age 17, and who refused to confirm afterward that he will continue fighting, called Walters “an amazing fighter, an amazing champion.”

Donaire (33-3) said he had never tried harder.

“I was at my best, but he was too big, too strong,” Donaire said, “and he beat the ... out of me.”

Walters, 27, is 25-0 with 21 knockouts. He is from Jamaica and carries the nickname “Axe Man,” because that is the weapon he is appearing to use on his opponents as they fall to the canvas. All he needs now is a deep-throated “Timber.”

He called Donaire a great champion — “a super, super fighter” — and thanked him for the fight.

He added later, “I took a really bad shot in the second round. But I’m bigger, stronger, faster and more intelligent. That’s why I won the fight.”

A prime example of that size discrepancy was Walters’ 73-inch reach, five inches more than “The Philippine Flash,” Donaire.