Five-division champion Claressa Shields outclassed Kaye Scott before stopping her in the sixth round to win the WBA and WBC middleweight titles Saturday night at State Farm Arena in Atlanta.

Shields (19-0, 4 KOs) was fighting at 160 pounds for the first time in three years. She gave up the WBA and WBC belts when she moved to heavyweight (175), at which she became undisputed champion.

The knockout was only the second for Shields in the past nine years, which was particularly gratifying for her.

And the victory sets up a massive matchup with 147-pound champ and fellow Olympic gold medalist Lauren Price, who has agreed to move to 160 pounds to meet Shields, although no contracts have been signed.

"This was a hard camp," Shields said immediately after the fight. "I always say to myself that everything is easy work, but this was a hard camp. I cut 38 pounds. I started 14 weeks ago at 198 and got down to 160.

"It was a hard card. I think this is the most discipline I've been since the Olympics."

If Shields (19-0, 3 KOs) felt the effects of moving down to middleweight on fight night, it wasn’t reflected in her performance.

The 31-year-old from Flint, Michigan, overwhelmed Scott (5-2-1, 0 KOs) with her superior speed and ability, picking the Australian apart from both the outside and inside when Scott forced the action.

Scott tried to match fire with fire, but she simply doesn’t have the tools to compete with one of the greatest females of all time, whose skill set is off the charts.

Shields was unable to seriously hurt Scott through five rounds but hard punches to both the head and body evidently wore down the 42-year-old from Sydney, who had won her titles by outpointing Olivia Curry in December.

Scott was ripe for a stoppage in the sixth, which is when a brutal left hook and follow up overhand right from Shields sent her stumbling into the ropes for a knock down.

Referee Joel Scobie ruled that Scott could continue but only a few more shots from Shields convinced the champion’s handlers to throw in three towels simultaneously, which ended the one-sided fight at 1:38 of the sixth round.

And Shields, craving a stoppage, couldn’t have been happier than the moment she saw the towels as she beamed with excitement.

"I started going to the body to break her down," Shields said. "... All the girls are super tough to go 10 rounds. (But) I could see that the right hand was landing to her body. I just tried to get close, take my time with my shots, I threw a right, hook, right and she started wobbling and going down.

"... I just came out to show by I'm No. 1 pound for pound."

Now she can look forward to a more significant test. Shields vs. Price (10-0, 2 KOs) would be one of the biggest possible matchups in boxing, pitting unbeaten former Olympic champions against one another.

Shields is No. 2 on The Ring’s pound-for-pound list, Price No. 8.

Price would have to move up two weight classes to face a future first ballot Hall of Famer, which would be a daunting challenge, but obviously she’s willing to do so because of the magnitude of the event.

And it’s clear that Shields is enthusiastic about the matchup, as she climbed into the ring to face off with Price after the Welsh star outpointed Stephanie Pineiro in April, which was the first marketing salvo to promote the event.

The will be exchanging punches the next time they meet if they can come to terms.