Cletus Seldin looks on against Roberto Ortiz during their junior...

Cletus Seldin looks on against Roberto Ortiz during their junior welterweight bout at Nassau Coliseum on Nov. 11, 2017. Credit: Getty Images/Al Bello

It was five weeks ago when Cletus Seldin made his HBO boxing debut. He planned on celebrating his sensational knockout by flying to Florida to attend a wedding and then embark on a week-long vacation. Seldin was two days into the trip when his plans changed.

HBO wanted him back in the ring and on their network on Dec. 16. Seldin didn’t even pause to think about it.

“The second they told me, ‘HBO wants you back,’ I said ‘Yes, absolutely, yes, book the fight,’ ” said Seldin, a 31-year-old junior welterweight known as “The Hebrew Hammer.” “I don’t want to waste an opportunity because it might not come around again. If I’m not injured or hurt, I want to fight.”

Seldin (21-0, 17 KOs) will fight Yves Ulysse Jr. (14-1, 9 KOs) Saturday at the Place Bell in Laval, Quebec, Canada.

Seldin’s fight opens the HBO broadcast at 9:40 p.m. The card is headlined by Billy Joe Saunders defending his WBO middleweight title against David Lemieux.

Seldin, who was raised in Shirley and lives in Bay Shore, becomes just the third fighter in HBO’s storied boxing history to be featured on the network in consecutive months. The other two? Mike Tyson in 1986 and Roy Jones Jr. in 1996.

“Cletus is really something special, he’s a throwback to the fighters of the 1920s, 1930s,” said his promoter Joe DeGuardia. “It’s what the fans want to see. I expect fireworks.”

Seldin stole the show in his HBO debut at Nassau Coliseum on Nov. 11. Seldin dropped once-defeated Mexican contender Roberto Ortiz twice in the first round and opened a bad cut above Ortiz’s left eye. The fight was stopped in the third round.

“Some of these more modern fighters want to fight every six months but I’m a throwback to a different era when top fighters fought much more often,” said Seldin. “I truly want to fight every month so it was easy to get back in the ring so quickly.”

Seldin said when he was packing for the trip to Canada he noticed Ortiz’s dried blood on his boxing shoes. “It was like a badge of honor,” he said.

Ulysse Jr. is arguably the best fighter Seldin will have faced as a pro. He was a Canadian national champion and an alternate on the 2012 Olympic team.

“He’s all the things that people in modern boxing think of when they talk about what makes a successful boxer,” said Seldin of Ulysse. “My job is to make sure I ruin that for everyone. Just watch. Watch me. I will sacrifice everything for your entertainment.”

More boxing news