NEW YORK, N.Y. — Just when Ivan Calderon’s junior flyweight title defense against Rodel Mayol was beginning to heat up, the bout was stopped midway through the sixth round because of a bad cut suffered by the champion.

The co-feature to the Miguel Cotto-Joshua Clottey fight Saturday went to the scorecards — as opposed to being declared a no-contest — because it ended on a cut that was caused by an accidental clash of heads.

Had the scheduled 12-rounder been halted before the completion of four rounds it would have been a no-contest.

Calderon, the holder of THE RING and WBO 108-pound titles, was up by two points (58-56) on one scorecard. Mayol, the gutsy challenger from the Philippines, was up by two points (58-56) on the second scorecard. The third judge had the fight even (57-57). Thus, Calderon (32-0-1, 6 knockouts) retained his recognition as the world 108-pound champ by a technical split-draw verdict.

It wasn’t the result that Calderon, who suffered a nasty bleeding gash in the middle of his forehead after accidental headbutts in rounds five and six, was looking for.

The 34-year-old southpaw stylist from Puerto Rico is considered one of the best pure boxers in the sport by many boxing writers and hardcore fans. However, he has had a difficult time gaining crossover attention and live U.S. TV exposure because of his lack of aggression and power.

Calderon wasn’t able to make a case for himself to casual fans or network executives in the early rounds against Mayol (25-3-1, 19 KOs), whose four-inch height advantage and longer reach gave him trouble.

Although Calderon’s lateral and upper-body movement enabled him to avoid most of Mayol’s jabs and power shots, the veteran wasn’t able to land much himself while he was trying to find the proper distance to unload on his aggressive challenger.

Calderon may have been rusty from 10 months of inactivity since his last bout, a technical decision against Hugo Cazares that was also stopped prematurely because of a cut he suffered.

After three rounds of merely avoiding punches, Calderon began to find his rhythm in the fourth round, sticking and moving effectively against Mayol, who appeared frustrated.

In the fifth round, the fighters twice clashed heads, opening the cut on Calderon’s forehead. The laceration was twice examined by the ringside physician, who allowed the fight to continue. Each time Calderon left the neutral corner where he was examined, he abandoned his cautious style and attacked Mayol, landing hard lefts to his foe’s head.

Mayol relished the change in Calderon’s tactics.

However, just when it looked like a decent scrap might develop, another accidental headbutt opened Calderon’s cut up to the extent that the ringside physician called the fight off at 1:50 of the sixth round.

“I came in slow and he came in fast,” Calderon said after the fight. “He came in low with his head down when I got the head butt and cut. I saw a lot of blood after the second head butt but then the action picked up.

“The fight was going the way I wanted. It was back and forth and still even, but I was starting to get hot, throwing more punches.”

Calderon’s Filipino challenger thought he threw most of the punches in the completed five rounds.

“I’m very disappointed, I thought I won the fight,” said Mayol. “When (Calderon) heals up I want to fight him again.”

In the main undercard bout, Russian middleweight prospect Matt Korobov (6-0, 5 KOs) was forced to go the distance for the first time in his promising pro career by tough Loren Myers (7-3, 2 KOs).

Korobov easily outpointed Myers in their four-round bout, winning by unanimous scores of 40-36, but the a young journeyman from Fresno, Calif. showed guts by pressing the Russian amateur star and 2008 Olympian in rounds three and four.

In other undercard action, Jorge Diaz (9-0, 5 KOs) won a hard-fought unanimous decision over tough Guadalupe Deleon (7-7, 4 KOs) in a six-round junior featherweight bout that looked to be a blowout early but developed into a crowd-pleasing brawl.

Diaz, who won by scores of 58-54 and 59-53 (twice), dropped DeLeon twice in the first round, but the gutsy Texas-based Mexican survived and battled back hard whenever Diaz pressed him to the ropes in rounds two, three, and four.

By the fifth round, Diaz, a Puerto Rican based in Jersey City, N.J., had tired out enough for DeLeon to come of the ropes and engage with the prospect in the middle of the ring. The two went toe to toe in the final round and DeLeon appeared to buzz Diaz with about 20 seconds left in the bout.

Another Puerto Rican junior featherweight prospect, Jayson Velez (9-0, 8 KOs), knocked out Jesus Brown (5-2, 4 KOs) in the fourth round a scheduled six rounder. Velez, of Juncos, P.R., dropped Bayron, of Hormigueros, P.R., twice in round three. The referee stopped the fight 33 seconds into the fourth round.

Rafael Guzman, a featherweight prospect from Guadalajara, Mexico, struggled to a six-round split decision over Chicago’s Juan Carlos Martinez (14-10-1, 5 KOs). Guzman (22-1, 16 KOs) was able to frustrate Martinez with constant movement, but he was never able to get any respect from the tough journeyman. Guzman won with scores of 59-55 and 58-56. The third judges scored it 58-56 for Martinez.

Puerto Rican lightweight prospect Alberto Cruz (5-0, 4 KOs) stopped Rudy Valdez (2-5, 1 KOs) after two completed rounds. Idaho’s Valdez failed to answer the bell for the third round.

Doug Fischer can be reached at [email protected]