Yes you do otherwise it will clog and you will have a very heavy pot full of near boiling liquid (ask me how I know this). use a hop bag and then just whirl pool for the hot break and you should be fine that is what I normally do anyways.
I second the hop bag. Go to Lowes or Home Depot and pick up a few cheap paint bucket strainers. They are the exact same thing that you would buy from a homebrew shop for like 1/4 the price. They only last for a few brews but they are cheap enough to throw away.
My current brews...
MiniBrew 6.5 - Firestone Pale 31 Clone (oaked) 5 Gal Secondary - Empty