UFC insider Ariel Helwani reported Jones failed a drug test back in June. No word on the substance but the USADA could end up suspending Jones for two years.
White: Jones might get two years for this (via USADA).— Ariel Helwani (@arielhelwani) July 7, 2016
What a huge blow to the UFC just days before the fight. There is no time to find a replacement to fight DC. So the UFC was forced to move Mark Hunt's knockout of Brock Lesnar to the main event.