The last time Roy Jones Jr. ventured into the ring — a place he used to rule absolutely — he was knocked out colder than a plate of sashimi.

A former world champion in four weight classes, Jones was a still life on canvas that May night in Moscow, motionless for more than a minute following a 10th-round flurry of punches by Russian cruiserweight Denis Lebedev.

He is upright again and, in the tradition of so many champions who fight on through the blunt warning signs of decline, seems reluctant to give up the game, even at 42.

Which brings him to Saturday night at the Atlanta Civic Center, where he is scheduled to fight Max Alexander in a 10-round cruiserweight main event.

Jones is 54-8 with 40 knockouts. He has owned titles ranging from middleweight to heavyweight, beating the likes of Bernard Hopkins, James Toney, Mike McCallum and Antonio Tarver. In the mid-1990s prime of his career, Jones was recognized as boxing’s unofficial pound-for-pound best. No fighter of such pedigree has fought in Atlanta since Evander Holyfield dispatched Vaughn Bean at the Georgia Dome in 1998.

“I want to win the cruiserweight title,” Jones said, when asked what there is left for him to do in boxing. “I’ve won everything [middleweight, super middle, light heavy and heavyweight] but a cruiserweight title.”

“I think Roy just doesn’t want to go out on a loss,” McGee Wright, Jones’ adviser, told ESPN.com. “He wants to see how he feels and see if he wants to go any further.

“With Lebedev, he was in the fight until the last 10 seconds and Lebedev is the No. 1 contender. It ain’t like Roy can’t compete.”

Since Jones beat Tarver in their first light heavyweight fight in 2003, he has lost seven of his past 12 fights. In his past three appearances, he suffered a pair of knockout loses and a lopsided decision to Hopkins.

Hopkins is proof that there is life in boxing after 40. In May, at 46, he became the oldest fighter to win a title when he took the WBC light heavyweight belt. The temptation to fight on is heightened because of the current weakened state of the sport, the promoter of Saturday’s card at the Civic Center pointed out.

“Boxing is undisputedly slowing down,” said Adrian Patrick. “If this was an environment where you had a lot of younger guys coming up, where it was very competitive, a growth kind of business, then you may find different decisions by Roy Jones and other fighters around that age.

“There is a need for some type of spark in this sport. [Jones] gets a chance to see these fights all the time [working as an analyst for HBO], and in my opinion, he wants to fight because the opportunities are there.”

Concerns about Jones’ health have grown along with his loss total. The rounds — 414 over a 22-year pro career — add up, and the sum is seldom pretty. According to the executive director of the Georgia Athletic and Entertainment Commission, Andy Foster, Jones was required to pass brain, heart and eye exams in order to be licensed for Saturday’s fight.

“Licenses are tougher to get here than they used to be,” Foster said. “We have not licensed a lot of people for various reasons. And if we didn’t think this fight was somewhat competitive, the commission wouldn’t license it.”

Jones underwent an exhaustive physical at the Mayo Clinic in October, his adviser said.

Jones also added another trainer — Tom Yankello — to his camp, in an attempt to bolster his conditioning.

Jones’ opponent, while 12 years younger and three inches taller with a corresponding reach advantage, does not seem to pose much imminent danger. Alexander hasn’t won a fight since appearing on the 2007 reality series “The Contender,” going 0-5-1 in his past six outings. He has knockouts in only two of his 14 victories and hasn’t fought since October 2009.