Seal the Patch and Concrete
After patching the concrete, it's a good idea to seal it. Concrete easily absorbs stains, and sealing will prevent that. There are more than a few products available for concrete sealing, but a heavy-duty water-based polyurethane is a good choice. If the floor has a rough finish, apply the polyurethane with a broom or brush using the bristles to work the sealer into the rough surface. With a smooth surface use a roller.
The beauty of water-based polyurethane is that it dries quickly, so you can put on a second coat just a few hours after the first. Also, water-based polyurethanes don't smell as bad as other types of sealer. In heavy traffic areas, it's a good idea to apply three or four coats.