CARBAJAL LOSES DECISION, IBF TITLE TO UNKNOWN PASTRANO.

Byline: Michael Rosenthal Daily News Staff Writer

So much for the much-anticipated matchup between mighty Lilliputians Michael Carbajal and Ricardo Lopez.

Carbajal, who was expected to fight the unbeaten strawweight champion this year, lost a split decision and his IBF light flyweight title to unknown Colombian Mauricio Pastrano on the undercard of the Oscar De La Hoya-Miguel Angel Gonzalez fight here Saturday.

The loss was Carbajal's first to anyone other than former champion Chiquita Gonzalez.

Pastrano (16-0, with 13 knockouts) seemed to waste a golden opportunity when he staggered Carbajal (42-2, 29 KO's) with a right in the third round but failed to attack, allowing the champion to recover.

However, it made no difference in the end. Pastrano, backpedaling and then striking effectively with quick combinations through most of the fight, consistently beat Carbajal to the punch.

And as the fight wore on, Carbajal, who suffered a cut above his left eye, seemed to tire while Pastrano maintained his intensity and punch volume.

Still, the decision was close: One judge had Carbajal winning 116-112, the other two gave Pastrano the edge, 115-114 and 115-113.

Carbajal didn't argue with the decision.

``He had a strong right hand,'' Carbajal said. ``He got me good in the third round. At the end, I tried to take him out with every punch, but it never came.''

Pastrano, who said he'd give Carbajal a rematch, was cocky afterward.

``I thought it would be a tougher fight,'' he said. ``I was never hurt. I used my intelligence.''

Carbajal weighed 108 pounds, Pastrano 106-1/2.

Also, Kostya Tszyu retained his IBF junior welterweight title but lost his perfect record when his bout with Leonardo Mas was called a technical draw.

Tszyu (18-0-1, 14 KO's) apparently dislocated Mas' jaw when Mas (23-2-1, 15 KO's) ran into Tszyu's shoulder as the two collided. Seconds later, as the referee tried to break the fighters, Tszyu hit Mas with one last punch - an accidental illegal blow - after which Mas couldn't continue and the fight was stopped.

Eric ``Butterbean'' Esch (26-1, 22 KO's) knocked out Curt Allan (5-1-1, three KO's) at 2:56 of the third round in a scheduled four-round heavyweight bout.

Floyd Mayweather (3-0, two KO's), a silver medalist in the Atlanta Olympics, stopped pathetically overmatched Jerry Cooper (6-4) 1:39 into a scheduled four-round super featherweight bout.

Unbeaten Stevie Johnston (20-0, 13 KO's) of Denver easily outpointed Jose Luis Baltazar (14-11, 11 KO's) in a 10-round lightweight bout.

And, in a scheduled six-round cruiserweight bout, Vassili Jirov, an Olympic gold medalist from Kazakhstan, stopped Vincent Brown (4-1, two KO's) at 1:29 of the second.