Mix together paprika, oregano, onion powder, garlic powder, salt and pepper and generously sprinkle on both sides of the roast. Place in the bottom of a slow cooker.
Add potatoes, carrots, celery and onions around the meat in the slow cooker. Whisk together broth and gravy mix and pour on top of vegetables and roast.
Cover and cook on low for 5-6 hours or until internal temperature reaches 130°F and 135°F for medium-rare .
When cooking is complete, remove meat and set aside on a serving plate. Use a slotted spoon to remove vegetables and place onto the serving plate with the roast. Cover with foil to keep warm.
Place remaining juice from the slow cooker into a saucepan. Add flour and whisk over medium high heat until gravy is thicker.