Betrayed by a team-member?

Maybe Whitebeard? It has been said Whitebeard was his equal, but it never mentioned whether Whitebeard was also his crewmember. Kinda like how Zoro and Luffy was to each other.

(May Contain spoiler to Kaizoku-Fansubs anime watcher to read below)
Either that or another marine we haven't seen before. The Top Admiral in the marines. We know of the great 3, which Aokiji is one of them, probably all 3 of them we're used to take down Gold Roger simultaneously.