MELBOURNE, Australia -- What many expected to be a mismatch between undisputed super lightweight champion Kostya Tszyu and 36-year-old challenger "Jesse" James Leija instead turned into a spirited championship bout between two wily veterans at the Telstra Dome on Sunday.

But in the end, it was Tszyu standing tall, as he retained his titles via a sixth-round TKO of Leija, who remained in his corner as the bell sounded for the seventh round.

A suspected broken eardrum was the culprit for Leija, who gave a good showing before the anticlimactic ending. The ringside judges didn't agree, having the champion ahead comfortably 58-56, 59-55 and 60-54 at the time of the stoppage.

"I'm sure it's busted," said Leija, now 43-6-2 with 17 KOs, of the eardrum. "My equilibrium was off and I wasn't sure where my footing was."

For Tszyu -- the reigning IBF, WBC and WBA champion -- it was another day at the office. The champion, fighting before over 30,000 hometown fans, was less than spectacular in victory, having some slow moments early on, but gradually taking control down the stretch.

Leija came out smart in the first round, throwing punches from long range and smothering Tszyu with clinches when the champ got too close. The challenger remained active in the second, accurately finding the mark with body shots, some stray low blows and the occasional right hand. As usual, Tszyu remained patient, waiting for his time to pounce.

Tszyu did indeed jump out of the corner for the third, but it was Leija who flurried, attacking the smiling champion along the ropes. With a minute left in the round, Tszyu landed his best punches of the fight, a right-hand left-hook combination that landed flush, but he didn't move the San Antonio native.

The fourth round was more of the same, with Tszyu upping the ante with some stiff right hands, but Leija refused to go away, throwing punch for punch with the hometown hero.

By the fifth, Tszyu's creeping pressure seemed to slow Leija, and though the challenger kept fighting, it was the champion who was gaining control.

As Leija walked back to his corner after the sixth with a nasty cut in the corner of his right eye, it was obvious that a conclusive victory for the Australia-based Russian was on the way. But there would be no knockout for Tszyu, as the injured eardrum (suspected to have been suffered after the fourth round) prompted the Leija corner to save their fighter from further punishment.

With the victory, the 33-year-old champion lifts his slate to 30-1 with 24 KOs.

In the Showtime co-feature, unbeaten prospect Muhammad Abdullaev kept climbing up the 140-pound ranks with a four-round drubbing of former lightweight champion Philip Holiday.

Abdullaev, an Olympic Gold Medallist in 2000, stormed out of his corner at the opening bell and refused to give Holiday room to breathe for the 9 minutes, 55 seconds the fight lasted.

Finding a comfortable home for his overhand right hand, Abdullaev struck early and often. Twice Holiday hit the deck in the first, but he was able to weather the storm and last through the opening stanza.

Keeping the pressure high in the second, Abdullaev sent Holiday to the deck early in the round, but referee Malcolm Bulner ruled the knockdown a slip. No matter, as Abdullaev kept attacking, using any and all tools at his disposal.

To his credit, Holiday kept fighting, but his lack of punching power proved to be no deterrent to his opponent's forward march. By the third round, Abdullaev was sending his foe backward with each right hand, and Holiday went back to his corner with a pronounced gash on his forehead.

The fourth-round finish was academic, as another perfect straight right by Abdullaev put Holiday on his back, where Bulner immediately called a halt to the bout over Holiday's protests.

Abdullaev, now 11-0 with nine KOs, takes home the WBO Intercontinental junior welterweight title with the victory. Holiday, a South African who now makes his home in Australia, falls to 38-6-1 with 22 KOs.