After 18 months out of the ring, Kalajdzic overcame two knockdowns in his seventh-round knockout of Oleksandr Gvozdyk on February 1 in Las Vegas. He’s making a much quicker turnaround this time around when he faces Richards in a 10-round light heavyweight bout in the co-main event of Zuffa Boxing 11 at Copper Box in London, live on Paramount+ in the US and Sky Sports in the UK.

“I had the 18-month layoff, so coming in, I had a lot of ring rust,” Kalajdzic told The Ring. “Now, I feel like I won't because I fought seven months ago. I'm still very fresh. I'm just ready to fight…I didn't think the ring rust had any effect until I actually experienced it, and it does a lot. Your distance, your timing, your rhythm, just everything – it's very different from sparring. I think I'll be much sharper and smoother in this fight.”

Kalajdzic (30-3, 22 KOs) was dropped in the first and fourth rounds by Gvozdyk. The Serbian light heavyweight finally began to find his rhythm in the sixth round, and the tide completely turned in the seventh.

Kalajdzic, 35, dropped Gvozdyk (21-3, 17 KOs) with a straight right hand and sent the Ukrainian to the canvas again moments later with another blistering right.

Gvozdyk rose to his feet but immediately fell back into a corner, prompting referee Ray Corona to stop the fight. While the first half of the fight wasn’t what Kalajdzic envisioned, he’s grateful for how he won and expects the momentum of the victory to carry into Saturday.

“The way I knocked him out and the way I came back gave me a lot of momentum,” Kalajdzic said. “If I had stopped him in the first two rounds, people would have been like, 'Oh, Gvozdyk is old.’ The way the fight happened and how sharp he looked before the knockout, I think it's given me a lot of momentum.”

Kalajdzic, who is ranked No. 3 by the WBO and No. 6 by the WBC, bills Richards (20-4-1, 13 KOs) as an “awkward and very durable” opponent. Three of Richards’ losses have come against the upper echelon of the light heavyweight division, as he was outpointed by The Ring, IBF, WBA and WBO light heavyweight titleholder Dmitry Bivol in May 2021, Joshua Buatsi in May 2022 and Willy Hutchinson in June 2024.

Buatsi (20-1, 13 KOs) is The Ring’s No. 5-ranked light heavyweight, while Hutchinson (20-2, 14 KOs) is No. 7.

With the light heavyweight division in flux thanks to the never-ending saga between Bivol, Artur Beterbiev and WBC titleholder David Benavidez, Kalajdzic believes the opportunity is there for someone to emerge at 175 pounds.

“I feel like just the doors open now for anybody in the top 10 to break out and do some crazy things,” Kalajdzic said. “Even with Beterbiev, they're talking about him and Bivol next year. Benavidez, I don't think he's moving down. He's just fighting at cruiserweight. The door is open for anybody to make a big move and do something.”