Did HMS Warrior and the ironclad frigates act as battleships?

Were HMS Warrior and other ironclad frigates really the battleships of their day?

For a short time they did the work of battleships by serving in the battle line, even though they were designated frigates.

The objection turns on what counts as a battleship in a period of rapid change. HMS Warrior and similar ironclad frigates kept a frigate designation while taking a place in the battle line for a brief period. Their capabilities gave them a fleet role that the older name might obscure. In the alternate cruiser case, a ship can remain a cruiser and still force an opponent to bring a capital ship to defeat it.