Leo Santa Cruz won a unanimous 12-round decision over Alberto Guevara in a showdown of Mexican unbeatens on Saturday to retain the International Boxing Federation bantamweight world title.
Judges gave Santa Cruz the victory by scores of 116-112, 118-110 and 119-109. Santa Cruz improved to 23-0 with one drawn, dropping Guevara to 16-1, but was disappointed in his performance, unable to deliver a knockout.
"I'm sorry I didn't do like I do. I'm sorry I didn't give you a good show," Santa Cruz told spectators after the bout. "But next time I will come back and give you what you want. I didn't feel like me."
Santa Cruz stretched his win streak to 21 fights in his fifth start of the year and the third defense of the vacant crown he won last June in a 12-round decision over South African southpaw Vusi Malinga.
Santa Cruz, who had stopped compatriot Victor Zaleta in the ninth round just 35 days earlier in his most recent prior bout, said too many fights this year might have hurt his performance.
But he also said he was unable to breathe through his nose after the third round, saying he thought it was only swollen and not broken.
Guevara, 22, moved around the ring early to trade punches with the champion, taking a hard left to the face in the third round but holding his own and proving elusive in the opening stages.
Santa Cruz, 24, began attacking Guevara more aggressively in the fifth round and opened a cut near the right eye of the challenger as well as delivering a right hook early in the seventh to stun Guevara as he began to seize command.
The bout at the Los Angeles Sports Arena was on the undercard of the fight between Britain's Amir Khan and unbeaten American Carlos Molina.