Aryna Sabalenka lost in straight sets to Nick Kyrgios in a Battle of the Sexes-style match that lacked the intensity and entertainment promised in the build-up.
Sabalenka, the women's world number one, was beaten 6-3 6-3 by 2022 Wimbledon runner-up Kyrgios, who is now ranked 671st after seeing the past few seasons decimated by career-threatening injury.
Both players hyped up the Dubai contest like a pair of boxers flogging a fight.
Sabalenka, 27, promised to "kick Nick's ass" as she promoted the event on US television chat shows, while 30-year-old Kyrgios insisted the razzmatazz of the occasion would bring new eyes to the sport.