Gennady Golovkin (33-0) wants a big shot

Gennady Golovkin might be the only man in boxing who loses every time he wins.

He did it again Saturday when he demolished Willie Monroe Jr. en route to an impressive sixth-round knockout in a middleweight title fight before 12,372 at the Forum. Golovkin remained unbeaten in 33 pro fights and retained his two world titles while extending a string of dominant performances that has seen him knock out his last 20 opponents.

But that’s also a problem for the punishing Golovkin, who is proving too good to get a chance at proving he’s great.

Golovkin has everything he needs to join Floyd Mayweather Jr., Miguel Cotto and Saul “Canelo” Alvarez as one of boxing’s elite stars: a fan-friendly style, an engaging personality and a really big punch. What he has lacked is a big-name opponent brave enough to share the ring with him.

And while Saturday’s destruction of Monroe showed why, Golovkin made it clear he’s done waiting.

“I am ready for the big fights. Miguel and Canelo. Right now,” said Golovkin who, at 33, considers time a bigger foe than any other boxer. “Not in the future. I am ready for the big fights right now. The next show.”

Cotto and Alvarez will probably think twice about accepting that offer given the way Golovkin started against Monroe, landing two lefts in the second round that sent the challenger to the canvas twice. Monroe showed uncommon courage by getting up both times, then rallied with a strong fourth round, raising a welt over Golovkin’s right eye.

But the former Kazakhstan Olympian, who has never been knocked down in nearly 400 pro and amateur bouts, didn’t quit, staggering Monroe again in the fifth and sixth rounds before another straight left to the face resulted in a third knockdown with less than a minute left in the sixth.

Monroe (19-2), of Rochester, N.Y., climbed to his feet, then turned to referee Jack Reiss and said, “I’m done.”

Golovkin, who knows a little something about knockouts since he’s won 30 of them, said Reiss was a little late. “He should have stopped it sooner,” he said. “[Monroe] was hurt.”

So now the waiting begins again for Golovkin, who has two of the middleweight division’s five championship belts — World Boxing Assn. and International Boxing Organization — but wants a chance to win the rest.

“I am the real champion. I want unification,” he said. “Let’s go. Let’s do it, guys. Who is No. 1 right now?

“Bring it on. I will show you.”

In the co-main event, Roman “Chocolatito” Gonzalez of Nicaragua retained his world flyweight title with a savage second-round knockout of Mexico’s Edgar Sosa.

Gonzalez (43-0, 37 KOs), considered by some to be a better pound-for-pound boxer than either Mayweather or Golovkin, backed Sosa against the ropes midway through the first round and unleashed a flurry of punches that eventually ended with Sosa dropping to a knee. That wasn’t ruled a knockdown, but the first two times Sosa went to the canvas in the second round were.

Gonzalez’s assault didn’t slow, though, so the backpedaling — and defenseless — Sosa was eventually trapped against the ropes and dropped again before the fight was mercifully stopped 23 seconds before the bell.

“I’m happy for my performance. My power was too much for him,” Gonzalez said in Spanish.

Gonzalez’s chief weapon was a strong right he used to repeatedly stun Sosa.

“He was good. He surprised me,” Sosa said.

Asked if Gonzalez was the best fighter he had ever faced, the 35-year-old Mexican said the bout ended too quickly to tell.

“Maybe if the fight went a few more rounds I could tell you,” he said.

kevin.baxter@latimes.com

Twitter: @kbaxter11

Times staff writer Lance Pugmire contributed to this report.