LAS VEGAS — Naoya Inoue and Ramon Cardenas proved to be the perfect palette cleanse Sunday night.

It was desperately desired, and frankly, demanded.

The Monster descended into Sin City seemingly having to play the role of super hero, forced to save the sport on the biggest weekend of the year from yet another night of boring boxing.

The assignment was clear — don’t play with your food and deliver another dull dance; unleash the detonating hands that demolish to avoid breaking punch stats futility; demonstrate the pulverizing power that is levels above everyone else; instead of running, run through the opponent.

On a weekend where stars like Canelo Alvarez, Ryan Garcia, Devin Haney, and Teofimo Lopez Jr. failed to satisfy the insatiable appetites of fight fans, it was the cab-driver-turned-contender Cardenas who rose to the occasion and delivered one of the most valiant and surprising performances in recent memory, knocking down Inoue in the second round and going toe-to-toe with an all-time great.

But it was the 122-pound undisputed champion Inoue who admirably answered adversity and scored a knockdown of his own to ultimately make mincemeat of Cardenas, serving hungry fans with a crushing eight-round technical knockout win in front of 8,474 at T-Mobile Arena.

And just like that, an unusually drab and damp day in Las Vegas was rewarded with a white hot fight of the year frontrunner.

The four-division champion and The Ring’s No. 2 pound-for-pound fighter, Inoue (30-0, 27 KOs) showed why he’s the most vicious and exhilarating knockout artist in the sport today by stopping the incredibly brave and upset-minded Cardenas (26-2, 14 KOs) for his 11th consecutive stoppage win in his 25th straight title fight.

Referee Thomas Taylor stopped the fight at the 45-second mark of the eighth as momentum massively shifted in Inoue’s favor with a mounting and mostly one-sided attack. The judges scored the fight exactly the same – 68-63 – giving Inoue every round except the second.

Inoue, a Japanese icon who came to America for his first true event, was a minus-10000 betting favorite according to BetMGM, but he played with fire once again and Cardenas nearly did to him what 42-1 underdog Buster Douglas did to Mike Tyson when he travelled to Tokyo in 1990 to pull off the shocker of the century.

“By watching tonight’s fight, everyone is well aware that I like to brawl,” said Inoue. “I was very surprised [at the knockdown], but I took things calmly and put myself together.

“The fans here were supportive and great. And I hope I was able to entertain them.”

After a fiery start, Cardenas faded and couldn't find the fairytale ending he'd envisioned. And just like he did after he got dropped by Luis Nery last year in May in front of a sold-out crowd at Tokyo Dome, Inoue rebounded from a nailbiter to notch the win.

“I never cared about losses. It’s about the best fighting the best," said Cardenas. “I dreamed about fighting in front of thousands of people in Las Vegas. So I came to give everything.”

After a calm first round, the fight shockingly turned in the second when Cardenas found lightning in a bottle and cracked Inoue with a vicious overhand counter left hand on the nose to knock down Inoue for the second time in his career.

Suddenly, a war broke out, and chants of “Mex-i-co” on the Cinco De Mayo Weekend showdown were drowned out by chants of “In-o-ue.”

“In the first round, I felt I had good distance. It got loose in the second round. From then on, I made sure to not take that punch again,” said Inoue.

Cardenas, a 29-year-old Mexican-American from San Antonio, Texas, showed that fights are not won on paper, stood toe to toe and valiantly traded with Inoue in the third, highlighted by a double right hand and a hard left.

Inoue made the WBA No. 1-rated Cardenas, who swung and missed with left hooks, pay tremendously in the final minute of the fourth. Inoue outlanded him 29-9 in the round while throwing 80 punches.

Inoue kept piling on the pressure in the fifth with his ferocious right hand, but Cardenas answered in the final seconds with a thudding body shot.

The sixth round featured an elite offensive attack from Inoue in the final 90 seconds as he went for the finish. Cardenas sat on the ropes, smiled and tried to bait him with home run swings. But by this point his bat was missing and he was no longer pitching a perfect game. Inoue pulverized Cardenas with 48 of 90 (33 power) shots while Cardenas mustered 14 of his own.

Inoue looked for the finish in the seventh and nearly got it when he knocked down Cardenas after several unanswered shots in the final 30 seconds. Cardenas slumped and fell in the corner, but he got back up and told referee Taylor "I'm good" as the bell sounded.

But he wasn’t.

In the eighth round, things were clearly not going well for the defenseless Cardenas, and one-way action forced Taylor to step in and stop the action.

“I told my trainer [Joel Diaz] that if I’m going out, then I’m going to go out on my shield. That’s what I did,” said Cardenas. “I’m not sad. But I’m bummed."

Inoue landed 176 of 462 in the firefight, while Cardenas connected with 80 of 290 shots.

“Odds-wise, I knew it was far apart,” said Inoue. “But I knew he was tough. But boxing is not that easy.”

Inoue’s carefully planned future can come into serious question moving forward anytime he faces credible competition.

Inoue, 32, moves on to face Murodjon Akhmadaliev on Sept. 14 in Tokyo, and perhaps WBA featherweight champion Nick Ball in December during a Riyadh Season show and after that his countryman Junto Nakatani, a knockout artist and The Ring’s No. 8 rated P4P fighter.

The Monster survived a serious scare, for now.