UFC 264: One win in nearly five years: What's gone missing for Conor McGregor?

On April 6, 2013, MMA coach Mark Henry was at Ericsson Global Arena in Stockholm to corner one of his fighters. It was the same card that featured the UFC debut of Conor McGregor.

McGregor earned a KO-of-the-night bonus with a first-round stoppage of Marcus Brimage. Henry, watching from the locker room, was floored by the performance.

Henry was so impressed that he later called a manager whose fighter was angling to be McGregor's next opponent, and he told the manager to avoid McGregor at all costs.

"This might be some of the best striking I've ever seen in MMA," Henry recalled thinking that night. "I was like, 'That might be the best fighter with movement and angles and speed and just knowing…