Ruiz (35-2-1, 22 KOs), who signed with Eddie Hearn’s Matchroom last week, hasn’t fought since battling Jarrell Miller to a majority draw in August 2024. The 36-year-old is looking to restart his career after injuries and inactivity stalled the momentum he built from his stunning upset of Anthony Joshua in 2019.

Knyba (17-1, 11 KOs), a 6-foot-7 Polish heavyweight whose lone defeat came against Agit Kabayel in January in a fight for the interim WBC title. Before that setback, Knyba had won all 17 of his professional bouts.

“I’m going to be fighting in Newark, New Jersey on September 4, baby,” said Ruiz. “After we get this victory, I would love to fight all the guys that have the belts Oleksandr Usyk vacated, and we’re going to become a two-time champion next year, let’s get it.”

Knyba welcomed the opportunity to fight in front of another large New Jersey crowd.

“I can’t wait to be back at the Prudential Center, my second home,” said Knyba. “I’m excited to be back in the ring in front of the New Jersey and New York fans, and they will fill the seats with white and red.”

The co-feature matches another recent Matchroom signing, Vito Mielnicki Jr. (23-1, 13 KOs), against former world title challenger Austin “Ammo” Williams (20-2, 13 KOs) in a middleweight bout with major implications for both fighters. Newark prospect Zaquin Moses (7-0, 3 KOs) also returns home for his first scheduled eight-round contest.