About the time Michael Katsidis’ eye began to close so did Glen Hamada’s Saturday night.

There are few other ways to explain how the veteran judge arrived at a scorecard that had the bashed and bruised Australian lightweight defeating former world champion Juan Diaz, 115-113, at the Toyota Center in Houston. Simply put, what Hamada saw did not happen.

Fortunately, judges Levi Martinez (116-112) and Gale Van Hoy (a far too close 115-113 in the right direction) both had Diaz winning so he left the ring with a split decision but the only thing split about it was Katsidis’ lip, eye and cheek.

Diaz dominated the fight much of the night and although Katsidis began to throw and land a bit more often late in the fight if he won three rounds two would have been a gift. This is not to say Katsidis isn’t brave or that he didn’t fight well enough to remain on boxing’s big stage among 135 pounders. It’s just to point out that Glen Hamada needs to visit his optometrist immediately.

Diaz was in command of the ring all night, whether controlling the distance with a stinging jab that did a lot of damage and created his victory margin or beating Katsidis to the punch at close quarters with a nasty uppercut and short right hands. Katsidis spent most of his time bleeding or missing, as Diaz slipped under his hook or stepped away from his countering efforts with stylistic fervor.

How Hamada found a way to give Katsidis the last five rounds in light of all that is beyond human comprehension, although Brendon Smith, Katsidis’ cornerman and loyal liege, kept insisting in the corner that his fighter was winning. Mostly he was saying this as someone else was wiping his blood off his face.

Each fighter was coming off the first loss of his career so there was a redemptive air to what both were about at the Toyota Center. Diaz succeeded in his quest by virtue of a relentless technical assault that left Katsidis’ left eye slit open along the lid from the second round on, his mouth filling with blood from a cut lip and his right cheek swollen, purple and leaking a steady flow of blood down the side of his cheek.

Smith insisted all night that his man was doing just fine however at the same time Diaz appeared to be converting him into a punching bag with an Australian accent. Hamada upheld Smith’s judgment at a time when he should not have been encouraged in such folly. So it goes in boxing and women’s gymnastics.

Diaz (34-1, 17 KO) was nothing short of brilliant, literally boxing circles around Katsidis while repeatedly striking him with a hard, snappy jab, uppercuts at close quarters and right hands behind that jab. Together they left his right eye half closed and his face a grim reminder that boxing can be an unforgiving sport.

Diaz landed his hard jab nearly 400 times according to CompuBox scoring and that set the tone of the fight. That jab held Katsidis at bay, often seeming to baffle him into a trance through the first half of the fight.

“I was going to throw more combinations but the jab was working so good (he didn’t bother),’’ Diaz said after his hand was raised.

Katsidis (23-2, 20 KO) was the harder puncher but his power was ineffective. He never hurt Diaz and spent far too much of his time with his head snapping back or his fists immobilized by Diaz’s slick defense and hammering offense. Yet the more Diaz changed the shape and color of Katsidis’ face the more Hamada saw victory being written on it.

“I’m shocked this is what a judge said,’’ said HBO Boxing After Dark commentator Lennox Lewis after the decision was announced. “To me, he won every round.’’

Perhaps he did but in the end Juan Diaz barely won the fight … a fact Glen Hamada would be wise to be thankful for.

In the semi-main event, Rocky Juarez fought like a man well past his prime but he still found a way to overcome a consistent beating from Jorge Barrios to pull out a victory by slicing open the side of Barrios mouth after beating him down with body shots that suddenly seemed to empty Barrios’ tank in Round 9.

At that point, Barrios was in command of the action despite having had two points deducted for highly questionable low blows. But after Juarez began to land consistently to the body everything changed. Barrios (47-4-1, 34 KO) slowed, his mouth agape as he fought to suck in enough air to counteract his growing weariness.

He never succeeded and Juarez finally caught him with several nasty shots to the face as his mouth hung open in the 11th round. Suddenly Barrios was bleeding badly just as a short right hand to the ear sent him tumbling to the floor. When he arose, his mouth was spouting blood like a volcano spews ash and one look from the ringside physician midway through round 11 ended the thought of any further damage being done to him.

“I started off slow but once I started landing good body shots his punches weren’t effecting me as much,’’ Juarez (28-4, 20 KO) said. “Barrios is very dangerous. I knew I had to be careful, landing my body shots accurately and slowly pressuring him, pressuring him.’’

That is exactly what Rocky Juarez did, thereby transforming himself from the old man he seemed to have become in the fight’s first six or eight rounds into someone who probably won himself one last chance to win a world title or at least the opportunity to fight for one. If that happens, for his sake he should hope Glen Hamada has the night off.