Anthony Joshua Beats Wladimir Klitschko In A HeavyWeight Bout For The Ages.

LONDON — For 12 minutes, the worst fears of the boxing community were being realized. After years of heavyweight matches that failed to captivate, 90,000 people who had come to Wembley Stadium to see fireworks in the division’s most anticipated bout in 15 years were instead being treated to a jabbing contest.

And then the bell for the fifth round was struck.

The fight ended with the official coronation of a brilliant young star, Anthony Joshua of Britain — who retained his IBF heavyweight championship and won the vacant WBA championship with a dramatic 11th-round technical knockout.

But to get to that crowning moment, the heralded phenom was pushed to the limit by a future Hall of Famer, Wladimir Klitschko — who, in defeat, proved mightier than he ever had in victory.

The first third of the bout was entirely forgettable — an extended feeling-out period. Joshua (19-0, 19 knockouts) made efforts to get inside. But Klitschko kept his opponent at bay with his lengthy jab, as he has so often done over the course of his 69-fight career.

But Joshua began the fifth with a furious attack, which eventually floored Klitschko to the delight of the sold-out crowd.

The fight seemed as though it might be over right then. The 41-year-old Ukrainian Klitschko had finally tasted Joshua’s power. And Joshua, who had dispatched all of his previous opponents inside of seven rounds, appeared on his way to doing it again.

But Joshua eventually punched himself out. And Klitschko (64-5, 53 knockouts) showed remarkable courage by staying on his feet and then launching an attack of his own to close out the round — surviving not only the knockdown but a sizable cut above his left eye.

Joshua admitted to being a bit too aggressive in his attempt to close the show.

“It does take a lot of energy out of you to hit someone hard,” he said. “I just was trying to connect a bit too eagerly. And I used a lot of energy.”

His opponent could sense it. In the sixth, Klitschko landed a picture-perfect straight right hand to Joshua’s temple, and the young star instantly crashed to the canvas. The 27-year-old champion beat the count, but suddenly he was the one looking to survive.

Klitschko, for one, didn’t believe he would.

“I thought he wouldn’t get up,” Klitschko said. “He managed to get up. Respect.”

Klitschko was dominant through much of the seventh. But a left-right combination upstairs by Joshua in the closing seconds of that round appeared to help stabilize the fight.

And it gave Joshua the ability to pace himself in the eighth round, which he thought was the key to his victory.

“I just said to my coach that I took a round off to get my breath back,” Joshua said. “And now I’m going to bounce back.”

He found the range little by little over the next two rounds. And then in the 11th, just as he had in that remarkable fifth, Joshua attacked immediately. Within seconds, he threw a thundering right uppercut that marked the beginning of the end.

Klitschko went down immediately. He beat the count, but this time he could not summon the strength to fight back. He went down a second time and again stumbled to his feet. But at 2:25 of the 11th, referee David Fields had seen enough and stopped the fight.

A jubilant Joshua leapt atop the ropes, with the massive audience in a frenzy. His reign has officially begun.

“Sometimes you can be a phenomenal boxer, but boxing is about character,” Joshua said. “When you go into the trenches, that’s how you find out who you really are.”

Klitschko and Joshua delivered a classic on what was an important night for boxing — a sport desperately hoping to restore the luster to its most storied weight class. Saturday night’s bout was arguably the biggest heavyweight boxing showdown in 15 years — since Lennox Lewis squared off against Mike Tyson. That bout effectively ended the Lewis and Tyson heavyweight era. The Klitschko era soon followed — in which Wladimir and his brother, Vitali, were thoroughly dominant.

But they were largely saddled with inferior opposition over the course of their careers. And they sometimes fought in a style dismissed as boring — particularly Wladimir, who was almost always able to win his fights by keeping his distance and using his jab.

And now, with a thrilling victory on his ledger, Joshua is embracing his role as the flag bearer for the sport’s signature weight class.

“For boxing, I think they’re excited about the division,” Joshua said. “There’s no doubt about it.

Klitschko was less inclined to take a big picture view after the fight, but he still recognized the magnitude of the classic battle and didn’t seem too upset by the result.

“I didn’t get the belts,” Klitschko said, “but I don’t feel like I lost.”