at BKB 5 and won the fight via KO after Dan Breeze failed to respond in time to the 10 count. He expressed before the fight he wanted to fight BKB's undefeated, and biggest star, Middleweight Champion Jimmy "Celtic Warrior" Sweeney, and after the fight on 2 separate occasions nearly got into a fight with Sweeney and his entourage, even grabbing a butter knife at one point, with fellow former UFC fighters Shonie Carter, who recorded the altercation, and Wes Sims present at the scene. At BKB 6 on July 1, 2017 Guillard faced the "Undisputed King of Bare Knuckle" and its #1 star, Jimmy "Celtic Warrior" Sweeney. The fight was held at 12 stone (168 lbs). Guillard lost the bout by unanimous decision. Guillard had a rematch with Sweeney on September 9, 2017 at BKB 7. He again lost the bout by unanimous decision. Guillard fought again on November 4, 2017 against Leighton Brady, who stepped in on four days notice after Guillard's original opponent dropped out. Although dropped almost immediately at the beginning of the fight, Guillard came back and dropped his opponent several times, finally dropping Brady a final time in the third round, winning by TKO after Brady failed to get up in time for the 10 count. Guillard expressed in the post-fight interview he wanted a title shot in BKB at Lightweight. BKFC After the four-fight stint in BKB, Guillard made his promotional debut in BKFC against Isaac Vallie-Flagg at Bare Knuckle FC 7 on August 10, 2019. He lost the fight via technical knockout due to a hand injury that rendered him unable to continue after the third round. In his sophomore bout he faced Scott O'Shaughnessy at Bare Knuckle FC 16 on March 16, 2021. He lost the fight via first-minute knockout. He then faced Harris Stephenson at Bare Knuckle FC 20 on August 20, 2021. He lost the fight via disqualification in the second round due to an illegal blow that was ruled an intentional foul. Guillard faced Joe Riggs at BKFC Fight Night: Montana on October 9, 2021. He lost the fight via first-minute knockout, incurring significant facial fractures. On January 27, 2020, The Association of Boxing Commissions issued a news release concerning Guillard's expected fight at the BKFC: Knucklemania 2 event to take place on Feb 19 2020. In the release they stated that Florida Athletic Commission Executive Director Patrick