Michael McDonald details how ‘worst pain’ of his life led to retirement decision, still has ‘zero function’ in left bicep

In the end, Michael McDonald’s biggest rival was his own body.
A world-class bantamweight who competed for both Bellator and the UFC, McDonald announced his retirement from mixed martial arts last week at the age of 27, electing to hang up his gloves less than two months after his spectacular 53-second knockout of former Bellator champion Eduardo Dantas.McDonald was a contender in the 135-pound division from an early age, even challenging for the UFC bantamweight title in 2013, however re