The skilled and savvy Ivan Calderon keeps going, almost like a machine, winning fight after fight against all manner of styles. One wonders how long it will be before he slows down and — perish the thought — loses a fight. There was a hint of slippage when Calderon barely beat the Colombian Ronald Barrera a year ago, followed by a real scare when Hugo Cazares knocked him down, although he rallied to outsmart the bigger Mexican fighter.

On Saturday Calderon defends his WBO 108-pound title against a Puerto Rican rival, Nelson Dieppa, on a PPV show that I believe is available only in Puerto Rico.

Dieppa faces the problem that confounds all of Calderon’s opponents — how to hit him, and, if successful, to keep hitting him.

Calderon has Willie Pep-type moves, although executed in the southpaw style. He is truly a beautiful boxer.

I thought that the fiery young Mexican, Juan Esquer, had a good chance against him, but Calderon was too elusive and too clever although one of the judges made it a close fight. Esquer swung and missed, and Calderon hit and dodged.

That was Calderon’s 30th win in a row and his 15th successive world championship victory in two weight classes — 105 and 108 pounds. Such consistency is rare.

Dieppa, a former WBO junior bantam champion, gets the fight after an impressive stoppage win over Alex Sanchez in an all-Puerto Rican elimination bout when he beat up a fighter who had given Calderon a brisk 12-round tussle.

That was a big win for Dieppa after back-to-back losses. Although he is 37, he looked as good as he has ever done.

Dieppa is a heavy hitter and very experienced, and I think he will be doing his very best to keep the slick champion under pressure.

It is is perhaps a little ominous for Calderon that one of Dieppa’s biggest wins was against a speedy southpaw, the Colombian Kermin Guardia, whom he knocked out with a big right hand in the opening round. There is danger in Dieppa’s right hand, but Calderon knows this and he will be ever-watchful, as always.

A puncher always has a chance, but unless Dieppa can somehow land a perfect right hand the way he did against Guardia he seems booked for a long, frustrating night.

While Calderon's lack of serious hitting power is well known, he can get an opponent disheartened with the way he keeps popping away at them, and he seems able to box at a fast pace all through the 12 rounds. Dieppa, I feel, is likely to find himself bothered and bewildered, but he will keep trying, and while I am expecting a clear points win for Calderon I have a feeling that this could be one of his more difficult fights.

RESULT: Not difficult at all — Calderon wins shutout decision.