White made the announcement during the broadcast of the "Dana White Tuesday Night Contender Series," shortly after Hardy, 29, knocked out Austen Lane (2-0) in just 57 seconds in their heavyweight bout.
Details of Hardy's contract were not immediately known.
Hardy, of Millington, Tennessee, dropped Lane to his knee with a straight right hand. Lane, a former NFL player himself, immediately popped to his feet, only to eat a follow-up left hook that ended the fight.
Fighting out of American Top Team in Coconut Creek, Florida, Hardy went 3-0 as an amateur, with three first-round knockouts.
The UFC's decision to offer Hardy an opportunity on the contender series has been met with some criticism because of Hardy's past. He was exiled from the NFL in 2015 because of off-the-field legal issues involving domestic violence and drug possession.
Hardy was convicted of domestic violence in 2014, but the charges were later expunged from his record after the victim failed to appear in court for a jury trial during his appeal. Hardy has denied ever hitting a woman, but four dozen photographs of the woman that were evidence in the trial and later published online by Deadspin show bruises to the woman's chin, neck, arms, back, legs and feet.
In an interview Friday, Hardy referred to White as "an angel" for giving him an opportunity. White has stated Hardy has turned his life around and deserves a second chance.
Hardy is a former All-Pro defensive lineman who played for the Carolina Panthers and Dallas Cowboys.
Lane (2-1) suffered the first loss of his pro career. He was drafted by the Jacksonville Jaguars in 2010 and left the league in 2014.