Demetrious Johnson has announced his retirement from mixed martial arts The 38-year-old held the UFC flyweight championship between 2012 and 2018 Demetrious Johnson's illustrious career in mixed ...

Johnson is an investor in the young enterprise startup, which provides businesses with data and voice services. Founder and CEO Rick Crabbe got to know him while training at the same MMA gym.

Unfortunately for Brazil's finest, Johnson won't be swayed — no matter the offer presented. "There is no number," Johnson said when asked about a price he'd need to fight again.

Demetrious "Mighty Mouse" Johnson is calling it a career.. The former UFC flyweight champion, current ONE Championship flyweight champion and arguably one of the greatest mixed martial artists of ...