ATLANTIC CITY, N.J. -- In an anticlimactic main event that saw many patrons heading for the exits by round eight, Bernard Hopkins retained his undisputed middleweight crown with a 12-round unanimous decision win over a game but overmatched William Joppy.

Scores were 119-109, 118-109, 119-108 for Hopkins, who lifts his record to 43-2-1 with 31 KOs. Joppy falls to 34-3-1 with 25 KOs.

Hopkins made his 17th title defense in a fight that had little of the drama and color of the Spinks-Mayorga welterweight fight that preceded it.

The first two rounds were mainly fought at close quarters, with both fighters trying to establish their inside dominance and Hopkins edging Joppy in that battle, though not by a great margin.

Hopkins' punches -- to both the head and body -- started to get harder and more accurate in the third, and a low blow by Joppy seemed to fire "The Executioner" up even more.

By the fourth stanza, Hopkins began to break Joppy down, and with whatever rust he had out of his system, the Philadelphia native went to work.

Joppy hung tough, though, finding some success when he boxed and stuck Hopkins from long range. But you know Hopkins -- he just won't go away, and if he gets near you, he's touching you, whether it's on your jaw, your ribs, or your hips.

Hopkins put on an inside fighting clinic in the seventh and eighth rounds, and Joppy, though not visibly hurt, was definitely worn down by the attack. By round nine, the outcome was no longer in doubt, and though Joppy stood his ground and refused to back down from Hopkins, his choice to stay in the trenches with him was a bad one -- one that cost him the fight.

Continuing to press the attack into the championship rounds, Hopkins' battering showed on the swollen face of Joppy, and in the 12th Hopkins pulled out all the stops in search of a much promised knockout, drilling the courageous Joppy from corner to corner until the final bell.

Hopkins was never able to put Joppy down, though the 38-year-old had bet Joppy $50,000 he would knock him out. Despite taking some tremendous punishment, Joppy stayed upright.

"He earned that $50,000 that we bet but I did try to get him," Hopkins said. "The referee was brave for letting him keep going."

Information from The Associated Press was used in this report.