Anthony Joshua and Oleksandr Usyk will go face to face for the first time at a press conference at 1pm on Thursday - watch a live stream here.
Their world heavyweight championship fight is on Saturday at the Tottenham Hotspur Stadium, live on Sky Sports Box Office.
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Tickets are from only £40 for The SSE Arena, Wembley and Utilita Arena, Newcastle
"[Joshua] has to beat Oleksandr Usyk to keep the undisputed dream alive and he wasn't prepared to swerve the challenge of Oleksandr Usyk, he's not that kind of guy," promoter Eddie Hearn told Sky Sports News.
"[Usyk is] definitely, a top-five heavyweight in the world. Maybe the No 1 heavyweight in the world - this is the scary thing."
Lawrence Okolie defends his WBO cruiserweight title against Dilan Prasovic on an action-packed bill, which also includes the return of Callum Smith against Lenin Castillo at light-heavyweight.
Campbell Hatton pursues the fourth victory of his pro career, while Florian Marku challenges Maxim Prodan for the IBF international welterweight title.