LAS VEGAS – Gary Sheffield and his beautiful gospel-singing wife tried to get back to their life yesterday, after she trashed an alleged extortionist’s claims that she engaged in three-way sex.The couple stepped out in public for the first time last night since the lurid news broke, sitting four rows from ringside for a boxing match at the Mandalay Bay Hotel, where their longtime friend Winky Wright defended his WBC/WBA super welterweight title.

“I’m not going to really comment on what’s been going on,” said Sheffield. “I issued a statement and I’m just going to let that speak for us right now. I really don’t want to get into any of it.”

But his 28-year-old wife, DeLeon Richards, hit back on her Web site late Friday, trashing the claims that she was in a sex video with singer R. Kelly and another woman.

“The first thing I would like to say, I have never been involved in any acts concerning three people in my entire life nor would I ever,” Richards wrote on the site.

She did admit, however, that she had “strayed from the Lord,” and her mother told the Daily News last week that DeLeon had a teenaged romance with R. Kelly a decade ago.

“When I was a teenager, I strayed from the Lord and my upbringing for a short period but thanks to God’s loving Grace he quickly reeled me back in,” Richards wrote.

She apologized for “any of the things you have seen or heard in the media,” adding that she lives a clean life. “I cannot change what people think but only care about what God knows,” she wrote. “I have never used drugs. I have never drank alcohol nor have I ever smoked.”

Sheffield has stood by his wife after self-described community activist, Derrick Mosley, 38, allegedly approached Sheffield’s agent claiming to have a tape of Richards engaged in a ménage à trois and demanding $20,000.

The agent taped the call and Mosley was busted on extortion charges. Mosley has denied trying to blackmail the couple, saying he was just trying to help them.

Richards saw it very differently.

“This man did not care about us, only the money he thought he could get from us,” she wrote on her Web site. “He refused to produce any proof to substantiate anything he was saying against me. The only thing he cared about was convincing us he could make people believe these false charges.”

Authorities have not seen the tape and are not sure it even exists.

Asked last night how his family was dealing with the ordeal, Sheffield said, “We’re handling things fine. We’re doing okay.”