Place meat in a 5-qt. slow cooker. Add onions and celery. In a bowl, combine the ketchup, water, lemon juice, Worcestershire sauce, brown sugar, vinegar, salt, mustard, paprika, chill powder, pepper and hot pepper sauce. Pour over meat. Cover and cook on high for 6-8 hours.
Remove meat; cool slightly. Shred with a fork. Return to the sauce and heat through. Serve on rolls.