Off-topic, but how so? The Defiant was present during the roll call at the start of the battle, survived a running battle with the Cube for however many light years it is from the Typhon Sector to Earth and however long it took for the Enterprise to travel from the Neutral Zone to Earth, continued fighting throughout the last stand at Earth which saw many larger and likely newer vessels destroyed, survived largely intact, and was repaired and ready to serve again at DS9 soon after. Seems like a pretty good showing to me.
The Defiant only survived because Ira Behr threatened to ignore First Contact if it was destroyed.
Early drafts of the script of Star Trek: First Contact suggested that the Defiant was to be destroyed in the Battle of Sector 001. In the DVD commentary for the film, First Contact co-writer and Deep Space Nine producer Ronald D. Moore said that Deep Space Nine's Executive Producer Ira Steven Behr had seen the script and objected to the needless destruction of his ship in a story that didn't even involve the Deep Space Nine characters (apart from Worf). It would also prove to be inconvenient for the television show, so the Defiant was eventually allowed to survive the battle, and a line suggesting that the Defiant was "adrift, but salvageable" was added to clear up any ambiguity. No reference to the damage the Defiant received during the battle was ever made on Deep Space Nine (although a brief reference was made to the battle itself in "In Purgatory's Shadow", when Sisko mentions "the recent Borg attack").
I'm well aware of that, but I don't see how it's relevant to my point about what was actually shown in the final product onscreen.