Ihor Potieria

Ihor Potieria arrived in the UFC as a heavy-handed Ukrainian prospect, and he authored one of the more bittersweet moments in recent memory by knocking out MMA legend Mauricio "Shogun" Rua in Rua's retirement fight. It was the kind of headline that defines a career.

The rest of his run has been streaky. Potieria's power gives him a puncher's chance against anyone, but the division's better strikers and grapplers, like Carlos Ulberg, have exposed the gaps in his game. He's the type to alternate highlight knockouts with tough losses.

That volatility is part of the appeal. Potieria is a live underdog every time out, a fighter whose hands can change a night in an instant, as Shogun's farewell painfully proved.