The promotion announced Saturday that Askar was not medically cleared to compete in the featherweight contest. Askar, who made weight on Friday at 145 pounds, was a short notice replacement for Andre Ewell, who was removed from the event due to COVID-19 protocols.
UFC Fight Night 184 takes place at the UFC Apex in Las Vegas and is headlined by a heavyweight showdown between Alistair Overeem and Alexander Volkov. The card streams in its entirety on ESPN+.
Anchored at Midwest Training Center, the 26-year-old Askar was entering his Octagon debut on the strength of a three-round verdict over Kevin Wirth at LFA 92 this past October. Askar has won 11 of his 12 professional fights overall.
Stamann, meanwhile, last appeared at UFC on ESPN 13, where he dropped a unanimous decision against Jimmie Rivera.