CLEVELAND – Daniel Dubois didn’t need a single round to emphatically end his U.S. debut Sunday night.

The hard-hitting heavyweight contender from London dropped overmatched Joe Cusumano three times in the opening round and recorded an impressive first-round technical knockout on the Jake Paul-Tyron Woodley undercard at Rocket Mortgage FieldHouse.

Referee George Nichols stopped Dubois’ beatdown as soon as Cusumano went down for the third time with 53 seconds to go in the opening round. The official time of the stoppage was 2:10 of the first round.

Showtime Pay-Per-View televised Dubois’ easy victory as part of his new multi-fight agreement with that premium cable network.

Dubois (17-1, 16 KOs) won a second straight bout by quick knockout since his 10th-round knockout defeat to Joe Joyce last November 28 at Church House in London. The 23-year-old Dubois knocked out Romania's Bogdan Dinu (20-3, 16 KOs) in the second round of his comeback bout June 5 at Telford International Centre in Telford, England.

Cusumano (19-4, 17 KOs), of Danville, Virginia, hadn’t been knocked out before Sunday night, but Dubois was an enormous step up in competition for him.

Dubois’ right hand to the side of Cusumano’s head sent him to his gloves and knees 58 seconds into their fight. A stunned Cusumano got up, but a combination by Dubois dropped him again with 1:19 to go in the first round.

Cusumano courageously attempted to fight out of severe trouble, but Dubois drilled him with two more right hands and a left as he fell to the canvas for the third time.

Nichols quickly waved an end to the action after that third knockdown.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.