John Riel Casimero vowed to "surprise" Guillermo Rigondeaux with a knockout finish as early as the third round.

But it never happened and there wasn't a slugfest. Instead, Casimero and Rigondeaux, for almost the entirety of the match with the World Boxing Organization bantamweight belt at stake, seemed to play the game of tag.

In a crowd showered with lots of boos, Casimero scored a split decision win over Rigondeaux to retain his WBO bantamweight title at the Dignity Health Sports Park in Carson, California Sunday, Aug. 15 Manila time.

Judge Robert Hoyle handed Casimero 117-111, Daniel Sandoval had it 116-112 still for the Filipino, while Tim Cheatham scored in favor of Rigondeaux 115-113.

The 12-round brawl entered a loop with Casimero doing most of the chasing while Rigondeaux, fighting at his best in a technical approach, circled around the ring and waited for the perfect timing to unload a one-time, big-time counterpunch.

Clearly, the 32-year-old Casimero was desperately putting the pressure to land clear shots but to no avail.

Casimero saw this coming though, expressing his disappointment with the gentleman's agreement he had with Rigondeaux -- no running away from each other.

"I'm excited cos you know Rigondeaux is a good boxer. He's a two-time Olympic gold medalist so I'm worried cos he said 'no run,' said Casimero, who improved to a 31-4 record on top of 21 knockouts, in a post-match interview with Showtime's Jim Gray.

Coach Nonoy Neri had to intervene and said his prized student couldn't focus much on the fight before Sean Gibbons, president of Manny Pacquiao (MP) Promotions, also spoke on behalf of their champion.

"What he's saying is it's very frustrating, it's embarrassing. The man came in the best shape he can to come into a real fight, to give the fans what they want and that was embarrassing," said Gibbons. "They should hold up that man's purse (Rigondeaux). That was one of the worst displays of fights that I've ever seen. The champ agrees that that was the worst that a guy ever did," added Pacquiao's right-hand man.

As much as "Quadro Alas" is focused on knocking out Rigondeaux, it did not materialize as the 40-year-old Cuban boxer gave little to no openings on his end.

Still in awe but flashing a huge smile on his face, Casimero, who only landed 47 clean punches compared to Rigondeaux's 44, said his opponent showed "no fighting" but "always running."

Casimero caught fire as early in the first round, unloading a couple of left hooks and combinations, but couldn't sustain momentum due to Rigondeaux's merry-go-round routine and counterpunching.

The Ormoc native boxer would find himself hunting "The Jackal" only to be checked with some hooks and body shots before repeating the same tactic.

Casimero hauled more points in the fifth and ninth rounds, mixing it up with solid body shots and combinations as louder boos can be heard from the Carson crowd.

The Filipino slugger was credited with seven landed punches apiece while Rigondeaux emerged the most productive in the tenth round and marked the same number of clean shots.

Now that Rigondeaux is finished, Casimero made it clear, being the trash talker he is, to challenge WBC bantamweight champion and compatriot Nonito Donaire and Japanese icon Naoya Inoue, the unified super WBA, IBF and The Ring titleholder.

"This is my plan: three people. First, Rigondeaux finished. And second, Donaire. And next, f___ Inoue!" shouted Casimero, accompanied by Neri and Gibbons in the center ring, while slowly forming the middle finger gesture.

Casimero boasts a seven-match win streak after his second title defense while Rigondeaux suffered his second career loss with 20 wins and 13 KOs.