The 29 year-old from Gilroy, had Berto in trouble from the off, dropping him with some hard rights hands as the challenger struggled with the ferocious pace in the early stages of the contest.
More accurate punches put Berto down for a second time in the next round and left the former belt holder with a closing right eye that seemed to instantly trouble him as it blew up from a straight left.
From round three onwards the fight was much more competitive as the two fighters slugged it out on the inside and neither of the two warriors would give any ground for the remaining rounds.
Guerrero’s early knockdowns had made the result look more one-sided than it actually was as all three judges agreed with my card of 116-110 and this may not be the end of the matter between these two champions.
Earlier in the night, Keith Thurman Jr. improved to 19-0 with his 18th stoppage by halting an out-of-sorts Carlos Quintana in four rounds in what was a comprehensive victory to claim the WBO NABO 154lb belt.