In an Instagram post, the NIDCOM boss described the loss as a temporary setback
“Temporary set-backs can’t take winners off their course. AJ will return bigger, better and stronger.” she posted.
The defending champion, Joshua, lost his IBF, WBA, WBO heavyweight titles to the Ukrainian in front of a 65,000 crowd at Tottenham Hotspur Stadium.
Joshua had taken to social media shortly after his defeat, the second in his career after Andy Ruiz landed the first last year, to inspire himself and fans.
“Keep positive even if the world’s crumbling in front of you! London I love you & thank you each and every time!” the Nigerian-Briton wrote.
In an interview with BBC Radio 5 Live, Joshua’s promoter Eddie Hearn confirmed the boxer would trigger the rematch clause.
Hearn said his fighter had given Usyk too much respect and would have to make “fundamental changes” to regain his titles.
Joshua visited the hospital for medical attention after suffering a broken eye socket in the fight