Ukraine`s Vitali Klitschko retained his WBC heavyweight title with a 10th-round stoppage over the previously unbeaten Chris Arreola in Los Angeles, according to BBC.

Arreola, 28, failed to come out for the 11th round having been out-fought by his 38-year-old opponent who takes his record to 38 wins and two losses.

Klitschko dominated with his superior reach and despite a brief rally in the eighth round was rarely troubled.

"It`s never easy. You have to be at your best," said Klitschko.

Arreola had been unbeaten in 27 fights and was hoping to become the first Mexican-American to win a major heavyweight title.

He caught his opponent in the fourth and made an energetic start to the fight.

But despite his impressive work-rate he failed to overcome Klitschko`s superior reach, height and power and after getting a battering in rounds nine and 10 his night was over.

"I worked my butt off to be the champion but Vitali`s strong, he hits hard and I never wanted to quit. That`s never in me, I wanted to go the full 12 rounds," said Arreola.

"I couldn`t get to him, he was fighting the fight he was supposed to fight. He ran when he was supposed to and I just couldn`t get to him.

"Whatever I did he found a way to counteract that. He found a way to win and I found a way to lose."

Klitschko was fighting in the United States for the first time since defeating Britain`s Danny Williams in 2004.

And the Ukrainian admitted at being impressed with Arreola`s durability.

"Arreola had his chance, he had a great performance and I was very surprised," said Klitschko.

"He had a great chin and after my right hook, many opponents go to the floor but he still stayed up. Big respect.

"All my left jabs he was very well prepared for."