NEW YORK — Rafael Castillo is twice Adam Maca's age, but the British bantamweight prospect proved he is twice the fighter Saturday night.

Maca, 18, knocked Castillo around the ring for much of the four-plus minutes they fought on the Richardson Hitchins-George Kambosos Jr. undercard in The Theater at Madison Square Garden. Referee Arthur Mercante Jr. halted their scheduled four-round bout at 1:29 of the second round because Castillo wasn't reacting well to the punches Maca landed during the Brighton native's pro debut.

Castillo (3-6, 1 KO), of the Bronx, New York, was on his feet when Mercante determined he shouldn't continue. The 36-year-old lost a third straight bout by knockout or technical knockout.

"It felt unbelievable in there," Maca told DAZN’s Chris Mannix in the ring. "I come and I done what I came to do. I don't expect anything less from myself and I'm happy with my performance."

A right hand by Maca, who is promoted by Eddie Hearn’s Matchroom Boxing, seemed to cause a knockdown during the second round. Mercante ruled that Castillo fell to the canvas without getting hit.

The action continued only briefly once Castillo got up.

Maca controlled the action throughout the first round by landing an array of power punches. Maca connected with several flush punches in the opening minute of their bout, but Castillo took those shots well and taunted Maca.