Sakazuki

Admiral Akainu is a member of the Space Marines who previously held a rivalry with Juracule Mihawk.

History
Akainu was once considered to be one of the most powerful men in the galaxy. He held a rivalry with Juracule Mihawk for some time, but this rivalry was halted when they joined the Shichibukai and the Space Marines, respectively. Akainu has also claimed that Mihawk gained his incredible agility and spryness from training with a group of travelling clowns - a claim which Mihawk has not confirmed nor denied.