Story highlights NEW: Dewey Bozella, 52, defeated Larry Hopkins by unanimous decision

Dewey Bozella, 52, defeated Larry Hopkins by unanimous decision Bozella spent 26 years on a murder conviction overturned two years ago

The fight, at L.A.'s Staples Center, was Bozella's first professional bout

The main event features Bernard Hopkins, 46, against a man 17 years his junior

A 52-year-old cruiserweight who spent 26 years in prison for a murder he did not commit won his professional boxing debut Saturday night.

Dewey Bozella defeated Larry Hopkins by unanimous decision in the four-round match at the Staples Center in Los Angeles.

The pugilist served time in New York's Sing Sing prison after being found guilty of murder in 1983; his conviction was overturned two years ago.

According to a biography on his website, Bozella was offered several opportunities for an early release if he would admit guilt and show remorse.

"Anger at his imprisonment gave way to determination and instead of becoming embittered, he became a model prisoner" and earned several degrees, the site says.

President Barack Obama called Bozella this week, offering him encouragement in his fight.

JUST WATCHED The oldest world champion talks boxing Replay More Videos ... MUST WATCH The oldest world champion talks boxing 03:39

JUST WATCHED First pro fight as a free man Replay More Videos ... MUST WATCH First pro fight as a free man 05:00

During his incarceration, Bozella was crowned the Sing Sing heavyweight champion.

The main event Saturday night features Bernard Hopkins, 46, who first became a world champion 16 years ago. The American boxer made history in May when he was awarded a points victory over Canadian Jean Pascal to become the sport's oldest-ever holder of a global belt.

The World Boxing Council (WBC) light heavyweight champion was to defend his title against Chad Dawson late Saturday.

Hopkins is significantly older than his opponent. Dawson, currently ranked by Ring Magazine as the fourth-best light heavyweight in the world, is 29, 17 years younger than the Pennsylvania-born Hopkins.

Bozella's story resonated with Hopkins, who served a five-year stretch in Graterford Prison in Pennsylvania between 1983 and 1988.

So impressed was Hopkins with Bozella that he trained with the newcomer ahead of his much-anticipated fight.

"It inspired me," said Hopkins of Bozella. "He chose to do what he did, and not only did he get freedom, but he got humanity. An opportunity to do something that was taken from him years and years ago. To be on a major, major fight card.

"And now that we became, I can say friends, and have understanding about that dark place that I put myself in, you know, I wasn't innocent. But we still understand that dark place. Everybody has a story, but his is beyond a story."