A ball bat extending along an axis configured for hitting a ball. The bat including a handle portion, a barrel portion coupled to the handle portion, a tubular sleeve positioned within the barrel portion, and an end cap. The barrel portion includes proximal and distal end regions, and a central region. The end cap is coupled to the sleeve and to the barrel portion by an adhesive. The end cap includes an end wall and an annular wall proximally extending from an inner surface of the end wall. The annular wall is configured to engage an inner surface of a distal end region of the sleeve. The annular wall defines at least one through-wall opening configured for facilitating flow of the adhesive through and about the annular wall during the coupling of the end cap to the barrel portion.