Hard to believe Vitali Klitschko was once considered a quitter.

That was after his 2000 surrender to Chris Byrd in the 11th round of a fight he was winning handily. Suddenly, before the last round, Klitschko failed to get off his stool. His corner bustled for a minute before Byrd's hands were mysteriously raised in victory.

And the questions about his heart began.

It's hard to believe the current WBC heavyweight king – and the man generally considered the best big-man in boxing – was once looked upon as an Andrew Golota-type enigma. The reasons for his decision to stop fighting against Byrd seemed legitimate enough: He had a badly injured shoulder. But the boxing press had heard that before. And it pounced on him.

In retrospect, the attacks on Klitschko's character seem almost silly. The older of the two Klitschko brothers is hard-nosed and stout, as evidenced by his 2003 TKO loss to then-heavyweight king Lennox Lewis. Klitschko, obviously inspired by the need to restore his name, walked through Lewis's biggest punches without flinching. Even as Lewis turned his face into hamburger, Klitschko pressed forward – hoping his pressure would wear down the Englishman.

But, before Klitschko had a chance to see the results of his toughness, the fight was stopped. The native of Ukraine was enraged – and rightfully so. Lewis had ended the previous round in bad shape, slumping onto his seat like a drunk on a bar stool. Klitschko was surging. It was his big chance.

The opportunity was cut short. But the great performance ensured that he would get another. And the word “quitter” would never be associated with Klitschko again.

Since then, Klitschko has fought like a man on a mission. He wasted no time in ridding the ring of the elephant-like Kirk Johnson in December 2003. He took an overmatched opponent out like a top heavyweight is supposed to – with an intense focus and a couple of iron fists.

When Lewis retired, the WBC and “The Ring” magazine settled on Klitschko-Corrie Sanders as the battle for the vacant heavyweight title. It was an interesting storyline: Sanders had almost decapitated Klitschko's younger brother, Wladimir, in March 2003 in that year's biggest upset. Some felt like Sanders' southpaw style and punching power would do the same to Vitali.

It almost did. Sanders caught Klitschko early, rocking him with his signature right-left combination – the same combination that stunned Wladimir. But Vitali called on the same courage that allowed him to weather the Lewis storm almost a year earlier.

It was a courage and determination that was spawned from the disappointment of the Byrd loss.

Klitschko went on to stop Sanders in the eighth round of a wild shootout in Los Angeles. And though Klitschko will never be a Larry Holmes – like boxer/puncher with top-of-the-line tools, he has ability. He is similar to rival Lewis – who also had awkward growing pains on the way up before establishing himself as the best fighter of his era.

But it will take time for Klitschko to grow into the fighter Lewis eventually became. And fights against the likes of England's Danny Williams probably won't help. It's a no-win situation for the champion: If he wins, he's supposed to win.

If not, he's a disappointment.

But Lewis was faced with the same predicament through most of his career – a bizarre, inexplicable lack of respect despite a track record for knocking out his most dangerous opponents. It wasn't until Lewis did away with Tyson in 2002 that he finally earned some long-lasting regard.

Lewis eventually changed everybody's mind with his fists. Klitschko is on his way to doing the same.