Super middleweight world titlist Callum Smith’s first defense will come against former middleweight titlist Hassan N’Dam, one of his former sparring partners, Matchroom Boxing promoter Eddie Hearn announced Tuesday.

The fight, in the works in recent weeks, will serve as the co-feature for unified heavyweight world titlist Anthony Joshua’s United States’ debut against Andy Ruiz Jr. on June 1 (DAZN) at Madison Square Garden in New York.

“This is a huge platform and one that Callum fully deserves,” Hearn said. “He has established himself as the No. 1 168-pounder in the world. N’Dam always brings the action and I believe this will be a high-level fight with plenty of fire. The mega fights await Callum, and he can’t afford to slip up here.”

Smith (25-0, 18 KOs), 29, of England, won a 168-pound world title last September by knocking out countryman George Groves in the seventh round and sending him into retirement in the final of the World Boxing Super Series in Jeddah, Saudi Arabia.

Now Smith is headed to the U.S. to fight for the second time, having had his seventh professional fight in Carson, California, in 2014 — a first-round knockout win.

“I’ve had a good camp and I’m looking forward to walking to the ring as a world champion for the first time in my career,” Smith said. “I worked so hard to get where I am and now the task is to keep hold of my titles and target those big fights. To have my first defense at Madison Square Garden is going to be special and it’s another box ticked for me personally. People call it the ‘Mecca of Boxing’ and I’ve always seen it as a venue that I’d love to fight at one day. The minute that there was a chance of it happening I pushed to make sure that I could be part of this show.”

He will be a heavy favorite against N’Dam (37-3, 21 KOs), 35, a Cameroon native based in France who is coming off a majority decision win over former four-time title challenger Martin Murray in December. But N’Dam is also moving up in weight and had been knocked out in the seventh round of his previous bout challenging then-secondary middleweight titlist Ryota Murata in October 2017 in Japan.

“N’Dam is a good fighter and he’s a former world champion. He’s only lost to three top fighters and he’s got some great wins on his record,” Smith said. “I had him over in England to help me prepare for George Groves, so we know each other well. He’s a good mover, has good footwork and can move around the ring pretty well. Experience is on his side and he’s an awkward guy to face. Saying that, he’s definitely a fighter that I should beat and get rid of if I’m on my game.”

N’Dam lost his middleweight title to Peter Quillin by unanimous decision in 2012 in a fight in which Quillin knocked him down five times. N’Dam’s only other loss came by unanimous decision for a vacant middleweight title against David Lemieux, who knocked him down four times, in 2015.

N’Dam had been under consideration as the opponent to face former unified middleweight world champion Gennady Golovkin in his June 8 return in a 164-pound fight, but the assignment ultimately went to Steve Rolls, giving N’Dam a chance to snag the title opportunity.

“I am confident I will create a big surprise in New York,” said N’Dam, whose massive one-punch first-round knockout of Alfonso Blanco in an interim world title fight went down as the 2016 ESPN knockout of the year. “It is a true privilege for me to be given the chance to fight at Madison Square Garden for the first time in my life. At this stage of my career this is a beautiful opportunity for me to be able to change divisions and fight for [a world title].

“I am so pleased and proud for this opportunity to be offered to me and I would like to add that even though the challenge is a big one, this does not affect my focus and my determination. Callum Smith is an excellent boxer with many qualities as he is tall, he can impose his own boxing style on most of his opponents. I have much respect for him both as a boxer and a person. I believe it will be a very tactical fight. I have the experience of boxing on big shows as I have participated in many and in front of thousands of people. I have always defended my titles abroad and I am used to pressure, and know how to handle it.”