Examining Career of 'Mighty Mouse', Demetrious Johnson

He had a brilliant run in the sport, including a lengthy stint as the UFC Flyweight Champion from 2012 to 2018. Now is as good a time as any to take a look back at Johnson’s career as a fighter.

Demetrious Johnson: The Early Years in MMA

Born on Aug. 13, 1986, Demetrious Johnson turned to the world of sports when he was a three-sport athlete in his high school days in his home state of Washington. While enrolled at Washington High School in Parkland, WA, the man who would become “Mighty Mouse” competed in wrestling, cross-country, and track.

Inside the wrestling ring, Johnson starred in his junior and senior seasons, finishing in the top three in Washington State. While he was awarded scholarships to wrestle collegiately, he did not accept any of them and matriculated as a member of the Pierce College student body in Pierce County, WA.

After two years, Johnson departed from Pierce College and turned to MMA. All nine of his amateur contests in MMA took place inside his home state of Washington, with Demetrious Johnson emerging victorious every single time.

Following his 9-0 run in amateur MMA, “Mighty Mouse” turned professional in August of 2009. His first professional bout ended in successful fashion in Everett, WA, scoring a first-round submission by way of rear-naked choke versus Frankie Mendez. After, he traveled to Anchorage to meet Marshall Carlyle in AFC 67 in January of 2010, winning by second-round TKO.

A knockout win by head kick a month later netted Johnson a World Extreme Cagefighting (WEC) contract and his promotional debut in April of 2010. He went 2-1 under the WEC promotional banner before the promotion was merged with the UFC that fall.

Demetrious Johnson Joins UFC Following Merger

In early 2011, Johnson joined the UFC’s active roster. It was in Dana White’s promotion where he’d achieve his greatest career success. Upon going 2-1 to start his UFC tenure, including a failed bid at the UFC Bantamweight Championship, he’d move down to the flyweight ranks and enter the UFC Flyweight Tournament.

During the March 3, 2012 semifinal vs. Ian McCall, Johnson had been declared the winner by majority decision, at least initially. However, after further review of the judges’ scorecards later that night, the scores had been incorrectly tabulated.

Under tournament rules, any three-round semifinal that had been scored a draw would advance to a fourth round, but given that the error hadn’t been relayed to Dana White until after the show, a rematch was ordered for that June.

Johnson won unanimously in the rematch and later took the championship by way of unanimous decision versus Joseph Benavidez in Toronto. This began an amazing run as the titleholder at 125 for Demetrious Johnson, making 11 successful defenses of the belt.

Johnson Joins ONE Championship Following Trade

In 2018, the combat sports world was shook by something that you’d normally only see from the team-competitive sports. Demetrious Johnson was dealt away by the UFC to Singapore-based ONE Championship.

To complete the transaction, ONE Championship sent Ben Askren to the UFC. At the time of the trade, Ariel Helwani, then with ESPN, explained the trade thusly:

“Demetrious Johnson wants to move on,” Helwani began. “Demetrious Johnson lost his belt, right? He broke the record, it’s time to move on. And so, because he has some fights left on his contract, the UFC says ‘We’re not going to release you, but how about, if you want to go to ONE, where your head coach, Matt Hume works, he’s the vice president of operations, you want to go over there? We need something from these guys.'”

The trade worked out handsomely for Johnson and his camp. Their fighter went 5-1 under Chatri Sityodtong’s promotional banner, including a stint as ONE Flyweight (135 lbs) MMA Champion, won in a rematch versus Adriano Moraes in the inaugural ONE Championship event to be streamed in North America on Amazon Prime and defended in a trilogy match.

Demetrious Johnson Ends Career On Top

After the trilogy fight with Moraes, Demetrious Johnson kept busy with a series of grappling matches in 2024 during the Brazilian Jiu-Jitsu Pan American Championship. Upon winning the gold medal in the masters division at 154.6 lbs, he squared off against 248-lb Michael Sante Medina.

Johnson defeated Sante Medina inside the final moments of the contest. Late last summer, he appeared at ONE 168 in Denver to announce that he’d be retiring from MMA.

“I am done,” he said. “I am done competing in mixed martial arts and I want to thank you guys so much for giving me the opportunity.” In the immediate aftermath of Johnson’s retirement, Chatri Sityodtong revealed that “Mighty Mouse” would become the initial member of the ONE Championship Hall of Fame.

Final Thoughts

What were some of your favorite memories of Demetrious Johnson?