Originally Posted by
FireEmblem
Well, the marines aren't all faceless and nameless grunts. It wouldn't be too much to assume that a lot of marines of Captain rank are pretty strong. Considering that Smoker was leagues above Luffy on their first encounter, it wouldn't be too much to make a parallel between Smoker-Luffy and Garp-Roger. Garp was known for cornering Roger many times, and I see Smoker being that thing for Luffy at one point or another.
But aside from Smoker, I assume that yes, other Captains are at least as battle ready as a lot of hardened pirates. Not to mention things that rank higher than Captain.