Destroyer Units
From Memory Alpha, the free Star Trek reference
Several Destroyer Units, made up of Federation destroyers, were incorporated into the Starfleet fleet assembled by Benjamin Sisko to retake Deep Space 9, which was itself composed of elements of the Second and Fifth Fleets.
These Destroyer Units were responsible for protecting the waves of attack fighters that were targeting the Cardassian portion of the Dominion fleet.
After sending in the second wave of fighters, Sisko requested that Destroyer Unit 2 and Destroyer Unit 6 need to move in closer to give the fighters more cover fire, but also to be alert and avoid being outflanked.
Among the starship captains belonging to either these Destroyer Units were Captain Diego and Captain Reynolds, of the USS Centaur. (DS9: "Sacrifice of Angels")
