For 35 minutes, it was the dreariest of the dreary, a slow-motion sleeping pill of a fight.

But in the final minute of the twelfth round of one of the very worst title fights you’ll ever see, Shannon “The Cannon” Briggs, a career underachiever, put his massive frame to good use. Briggs, the soon-to-be 35-year-old asthmatic, smashed Sergei Liakhovich thru the ropes, onto the scorer’s table, and won the WBO heavyweight championship.

For the vast, vast majority of this fight, the only winners in this affair were the good people at Chase Field in Phoenix, Arizona who showed admirable class in not raining down a hellacious rain of boos on both athletes for performing in such a startlingly lackadaisical performance.

But Briggs, who no one could’ve predicted would be in the mix in the twelfth round, came to life.

He knocked the 30-year-old Liakhovch, the Belarus-born Arizona resident, to the canvas, with three right hands. The first one hurt him a bit, the second one a lot and the third sent him to the mat. Liakhovich got up at five, but he was wobbly and his eyes were unfocused.

With 26 seconds to go, Briggs, who has not been known for his stamina, got back to work.

He tossed a one-two that sent Liakhovich back into the ropes. Liakhovich bounced off the ropes and Briggs timed it, throwing a mean right to the gut that doubled the champion over.

He followed with a scoring left to the head, and two glancing blows.

Liakhovich toppled out, between the second and third ropes, onto the official’s table. Referee Bobby Ferrara didn’t bother giving Liakhovich time to re-enter the ring proper; he declared the bout over, at 2:59, Briggs, a congenial hulk of overflowing promise from Brownsville, Brooklyn, finally fulfilled his potential.

Briggs (48-4-1, 42 KOs) wasn’t at his best on this night, but his opponent, Liakhovich, was at his very worst.

Incredibly, he didn’t press the stamina-challenged Briggs, who weighed in at 268 pounds.

There is no real reason to dissect every round, as each one was a carbon copy, basically, of the last.

Liakhovich (23-2) was ahead 106-103, 106-103, 105-104 at the time of the stoppage, but this fight could have gone either way.

Briggs landed some telling blows to the head, while Liakhovich’s best work was his right to the body.

Briggs, an intensely likeable chap who will be a breathe of fresh air into the division, if for his engaging personality if not his ringwork, said he would have gone home and shot himself if he hadn’t pulled out the win.

Jim Gray, in his typical harsh fashion, summed up the 99% woeful, 1% scintillating fight, sparring with promoter Don King. Gray labeled the fight a severe stinker, and King disagreed vehemently.

To the promoter’s credit, that last half-minute was a thrilling theater.

For Liakhovich, there will be time to ponder why he performed so dreadfully after showing so much talent and heart in winning the title in April. For Briggs, next stop should be Jay Leno’s couch.