It's certainly not Alexander Povetkin, David Haye, Shannon Briggs, Wladimir Klitschko, Anthony Joshua or Tyson Fury.
So who is Andrzej Wawrzyk?
After turning pro in March 2006, Wawrzyk went 27-0 with 14 knockouts before being dispatched by Alexander Povetkin in the third round in May 2013.
He bounced back the following year with knockout wins over Danny Williams by first round TKO and former IBF world heavyweight champion Francois Botha. Williams and Botha, of course, were well past their respective primes.
In his most recent bout in September 2016, Wawrzyk defeated former world heavyweight title challenger Albert Sosnowski by sixth round TKO.
Wawrzyk is ranked the No 29 heavyweight in the world by BoxRec.
Deontay Wilder vs Andrzej Wawrzyk is essentially a tune-up for the former. However, Wawrzyk is on a six-fight win streak and has only lost to Povetkin, an elite heavyweight to say the least.
Should Wilder be victorious, it'll mark his fifth successful title defense. The WBC champ has defended his title against Chris Arreola, Artur Szpilka, Eric Molina and Johann Duhaupas.
Andrzej Wawrzyk facts and stats
Record: 33-1, 19 KO
Hometown: Krakow, Poland
Height: 6′5″/ 195cm
Reach: 79″/ 201cm
Promoter: Bullit Knockout Promotions
Andrzej Wawrzyk - highlights