The fight at the Citizens Bank Arena was not one of style but more of stamina, as the pair rumbled against the ropes over 12 rounds before Guerrero eventually broke the war of attrition.
The former featherweight and 130-pound titleholder won by decision with unanimous scores of 116-110 and marks Berto’s second loss in three fights.
“I told Andre I was going to beat him down. I had to keep my word. I had to fight him on the inside and work his body,” said Guerrero
“He didn’t hurt me at all. He caught me with a few shots. He’s a strong guy and he punched hard but I have a great chin.”
Berto was seen as the puncher of the fight and was the heavier man, but it was Guerrero who scored the knockdowns, dropping his opponent to the canvas in both rounds one and two.
Four shots to the face floored the former welterweight world champion in the first round, before two left-hand hits had the same effect in the second and forced his right eye nearly shut.
Berto had his back to the ropes for the majority of the fight and let loose with some dangerous uppercuts, and won the sixth, eighth and ninth rounds on all three scorecards.
But it was his counterpart who dictated most of the action, smothering the Haitian-American and never letting him fully extend his power punches.
Guerrero threw 731 punches to Berto's 411.
The victory makes the 29-year-old a strong candidate to be Floyd Mayweather Jr’s next opponent in the spring.
"Let's do this, Floyd," Guerrero said in the ring. "I got a victory against a great champion."
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