Heat olive oil in a large Dutch oven over medium-high heat. Sprinkle roast with salt and pepper. Add roast to pan, browning on all sides (about 8 minutes). Remove from pan. Add onion to pan; sauté 8 minutes or until browned. Return roast to pan. Combine broth, ketchup, and Worcestershire; pour over roast. Add tomato; bring to a simmer.