Eddie Hearn's Matchroom Boxing has signed the middleweight contender to a promotional deal, it was announced Saturday.

"White Magic" Mielnicki (23-1, 13 KOs) is a 24-year-old from Roseland, New Jersey, who turned pro while still in high school in 2019.

After entertaining an offer from Zuffa Boxing late last year, Mielnicki signed a promotional deal with Sampson Lewkowicz in December. But Mielnicki only had one fight with him, a 10-round unanimous decision win against Omar Huerta in April.

Mielnicki has also previously been tied to Bob Arum's Top Rank Boxing and Al Haymon's Premier Boxing Champions.

Mielnicki had a busy 2025 while making his middleweight debut. In November, he stopped Samuel Nmomah in nine rounds. Five months prior, Mielnicki beat Kamil Gardzielik in a 10-round unanimous decision. Three months before that, Mielnicki fought to a majority draw against Connor Coyle, which was later ruled a no-contest after it was learned that his opponent had tested positive for a banned substance.

A fight announcement is also imminent for Mielnicki, Matchroom said.

If Matchroom is inclined to make the fight in-house, a matchup against former middleweight world title challenger Austin "Ammo" Williams (20-2, 13 KOs) could make the most sense.

Manouk Akopyan is The Ring’s lead writer. Follow him on X and Instagram: @ManoukAkopyan