A wrap-around cable sleeve assembly for environmentally sealing a cable section includes a wrap-around sleeve and a cable mastic patch. The wrap-around sleeve has a longitudinally extending portion and opposed first and second longitudinal edges. The longitudinally extending portion defines a portion of a cable chamber extending around the cable section when the wrap-around sleeve is wrapped around the cable section. The cable mastic patch is disposed on an interior surface of the longitudinally extending portion and extends transversely across the longitudinally extending portion. The cable mastic patch is configured and positioned to engage the cable section and form a continuous environmental circumferential seal about the cable section when the wrap-around sleeve is wrapped around the cable section.