Boil a pot of water and cook linguine pasta according to package directions. Drain and set aside.
While pasta cooks, heat olive oil in a saucepan over medium high heat. Add diced onion, garlic, and chopped basil. Sauté until translucent, about 10 minutes. Add the celery and crush tomatoes. Simmer over low heat until the sauce thickens. Remove and set aside. (This sauce can be made one day ahead and refrigerated.)
To prepare the fish, preheat oven to 350 F. Pan fry the snapper fillet with salt & pepper for 2 minutes on each side. Place it in the preheated oven for another 3 minutes until done.
Serve pasta with marinara sauce and cooked Goldband snapper on top.