MANILA, Philippines -- Filipino Nonito Donaire retained his IBF flyweight title on Sunday, stopping American challenger Raul Martinez in the fourth round.
Donaire (21-1) pummeled Martinez (24-1) with rapid punches to the head, sending him to the canvas for a fourth time in the bout before the referee stopped the fight 2:42 into the fourth.
"I just did what I had to do," said the 26-year-old Donaire, who had vowed not to fail the big hometown crowd at Manila's Araneta Coliseum.
Donaire floored Martinez twice in the first round and once in the second. In the fourth round, Martinez took a sharp left uppercut and fell backward, prompting referee Pete Podgorski to stop the match. The Filipino crowd roared, chanting Donaire's name.
Martinez, from San Antonio, Texas, waved a Philippine flag after Donaire's victory.
Former Philippine president Joseph Estrada sat ringside and congratulated Donaire after the fight.
In another bout, American Brian Viloria (25-2) stopped Ulises Solis (28-2-2) of Mexico with a right to the jaw in the 11th round to become the new IBF light flyweight champion.
The Hawaii-born Viloria is of Philippine ancestry. He raised his arms in triumph and shed tears as Solis lay on the canvas.
"He's not a Filipino executioner no more. It ended today," the 28-year-old Viloria said of Solis, who had defeated three Filipino fighters in the last two years.
President Gloria Macapagal Arroyo's office said she was "ecstatic" over the victories by Donaire and Viloria, adding that Philippine boxing was going through a "renaissance."