Photos: Gennady Golovkin knocks out Marco Rubio

“I will fight anybody,” said Gennady Golovkin, who remained undefeated following his second-round victory over Marco Antonio Rubio at StubHub Center.  (Alex Gallardo / Associated Press)

Gennady Golovkin, right, throws a left jab at Marco Antonio Rubio during the first round at StubHub Center.  (Alex Gallardo / Associated Press)

Gennady Golovkin, left, is 31-0, with 28 of those victories coming by knockout, after defeating Marco Antonio Rubio at StubHub Center.  (Jonathan Moore / Getty Images)

Gennady Golovkin, right, is pushed to a corner by referee Jack Reiss after knocking down Marco Antonio Rubio during the second round.  (Alex Gallardo / Associated Press)

Referee Jack Reiss counts over Marco Antonio Rubio, who went down after taking a huge uppercut, then a left-handed overhand shot from Gennady Golovkin during the second round of their bout at StubHub Center.  (Jonathan Moore / Getty Images)

Marco Antonio Rubio got up just before the 10-count ended, but referee Jack Reiss waved him out during the second period against Gennady Golovkin at StubHub Center.   (Jonathan Moore / Getty Images)

“I got up, but the referee decided to stop it,” Marco Antonio Rubio, left, said of Jack Reiss following his bout with Gennady Golovkin at StubHub Center.  (Alex Gallardo / Associated Press)

Gennady Golovkin, right, hits Marco Antonio Rubio with a right en route to winning in the second round at StubHub Center.  (Alex Gallardo / Associated Press)

Gennady Golovkin, left, throws a punch against Marco Antonio Rubio at StubHub Center.  (Jonathan Moore / Getty Images)

Gennady Golovkin celebrates after stopping Marco Antonio Rubio in the second round for his 18th straight knockout victory.  (Jonathan Moore / Getty Images)

Gennady Golovkin, left, and Marco Antonio Rubio show some mutual respect after their WBC middleweight bout Saturday at StubHub Center.  (Jonathan Moore / Getty Images)

Nicolas Walters is known as the “Axe Man,” because that is the weapon he is appearing to use on his opponents, as they fall to the canvas.   (Jonathan Moore / Getty Images)

Nonito Donaire, left, fights Nicholas Walters at StubHub Center in 2014. The Filipino Donaire will face Jessie Magdaleno Nov. 5 in Las Vegas.  (Jonathan Moore / Getty Images)