OLEKSANDR USYK’S LONG-AWAITED debut among boxing’s big men has taken another turn but will at least go ahead as scheduled in Chicago on Saturday night.

The undefeated Ukrainian pound-for-pound star [16-0, 12KOs], who is the former undisputed champion a division below at cruiserweight, will now face American Chazz Witherspoon at Wintrust Arena after original opponent Tyrone Spong had two urine samples fail VADA tests.

While Spong maintains his innocence and will exercise his right to have his ‘B’ samples tested, the show will go on without him in the Windy City due to the Illinois State Athletic Commission revoking his right to fight on their turf.

Witherspoon [38-3 29KOs] is a second cousin of former two-time World heavyweight king Tim Witherspoon and his record has gone unblemished for five years, his last win coming in March in Atlantic City against Santiago Silgado (who was also stopped early by Spong a fight prior).

“I can’t wait to face Usyk in Chicago,” said Witherspoon. “I have been in training ready for a big fight, and it doesn’t get bigger than this. Oleksandr is stepping up to Heavyweight – and he’s going to find out that it’s a totally different game.

“I’ve won my last eight fights and I really feel that I’ve been waiting in the wings for a huge opportunity like this and I am going to put every ounce of myself into the fight on this massive stage.”

Ireland’s former world champion TJ Doheny also returns on the bill, as does Chicago native and former Katie Taylor opponent Jessica McCaskill who defends her two 140-pound world titles.