The former UFC fighter was suspended by the Kanas Athletic Commission (KAC) back in August 2016 after testing positive for a banned substance. Guillard failed an in-competition drug test after his bout with David Rickels on July 22, although the commission cannot lawfully release the substance Guillard failed for it has been said that he was popped for cocaine use.
Guillard (32–16–2-3NC) has struggled for a while now, missing weight against Donald Cerrone, losing to Jamie Varner and having his bout against Ross Pearson made a no contest as Pearson suffered an accidental knee and was unable to continue. In his final bout in the UFC, he lost to Michael Johnson via unanimous decision. He was subsequently released from the promotion after the fight.
Guillard would then fight in WSOF, winning his first fight by TKO he would then lose his next fight against Justin Gaethje in what was meant to be a title fight until Guillard missed weight. Guillard then joined Bellator, losing his first two fights and yet again he missed weight for his bout with Derek Campos before having his win against David Rickels overturned.
Guillard will come up against Chidi Njokuani (16-4-1NC) at Bellator 171. Njokuani is currently on a 6 fight win streak with 3 of those wins coming in Bellator. His most recent win came over Andre Fialho in just 21 seconds.