Also being the KOTC light heavyweight champion, Lopez was undefeated his last sixteen fights, which marked Johnson's most experienced opponent at the time.
Johnson recorded the upset, using his wrestling to defeat the much more experienced Lopez via unanimous decision and becoming the KOTC heavyweight champion in just only his fourth professional fight.
[2] Johnson made his first title defense against then prospect and future UFC light heavyweight champion Daniel Cormier at KOTC: Imminent Danger on August 13, 2010.
He lost the fight and KOTC heavyweight championship in the first round via rear-naked choke submission, resulting in his first professional loss.
[3] Johnson rebounded from his loss to Cormier by defeating Boban Simic via unanimous decision on November 13, 2010 at KOTC: Infusion.
Johnson eventually made his promotional debut against current UFC competitor Derrick Lewis at Bellator 46 on June 25, 2011.
[11] Johnson next faced Chris Lokteff at ONE Fighting Championship: Warrior Spirit on November 15, 2013.
[18] Johnson made his professional kickboxing debut on April 7, 2017 at SUPERKOMBAT World Grand Prix I 2017 in Bucharest, Romania, being defeated by TKO (doctor stoppage) in round 1.
If Johnson had won his bout against Lukasz Krupadziorow, he would have face Cătălin Moroșanu at SUPERKOMBAT World Grand Prix II 2017 in Madrid, Spain.
[28] Johnson faced Carlos Felipe on March 29, 2024 at ACA 173: Frolov vs. Yankovsky, winning the bout via split decision.