With the eyes of the great four-division champion Naoya Inoue watching from ringside, Bruce Carrington displayed the depth of his boxing IQ Saturday night by recording an eighth-round TKO of replacement opponent Brayan De Gracia at The Theater at Madison Square Garden in New York.

“He came to watch me,” said Carrington (12-0, 8 KOs), who saw undisputed junior featherweight champion Inoue wave to him following the destructive performance by the 27-year-old Brooklyn featherweight contender, ranked No. 4 by the WBO and No. 7 by the WBC.

There’s plenty of speculation that Japan’s Inoue (27-0, 24 KOs) will move to featherweight by 2025.

Carrington, who turned pro in January 2023, showed why his rise has been rapid with his finishing flurry, a barrage that prompted the referee to dart in and spare the no-longer-responsive De Gracia, of Panama, from further damage.

“Brayan came to fight, and his knockout ratio (25 in 34 bouts) shows he’s dangerous, but I have a lot of experience to get around that and break that down,” Carrington said. “He had a lot of will. More reason to break him down.”

De Gracia, 30, was summoned to replace Enrique Vivas on the card after Vivas couldn’t gain visa clearance in time to make the bout.

By destabilizing his replacement opponent, Carrington landed a fifth-round knockdown from a flurry closed by a right hand to the head. Just before the sequence, De Gracia began to bleed from the nose.

The blood was the most vivid example of how Carrington was weakening De Gracia, as the fighter’s legs weakened and his punching activity decreased.

Carrington was content to let De Gracia (29-4-1) be the early aggressor, and in the second round he seemed to unearth an opening by letting fly more power punches, including two hard lefts to the head.

Carrington then planted a head-jarring right in the third, and delivered a body shot, only to expose himself to a De Gracia power shot that added intrigue to the bout.

Because De Gracia was so eager to throw punches, he exposed himself to blows like the hard right that Carrington sent him to punctuate an exchange.

By the seventh, De Gracia was backpedaling after being ordered by his trainer to hold more in order to preserve himself from sustained damage.

It didn’t help. Carrington nearly knocked De Gracia through the ropes to end the seventh, landing a combination of two quick lefts and a hammering right to the head.