A sport ball includes a casing forming an exterior surface thereof. The casing has a plurality of joined panels forming a partially-assembled casing and defining an open area. A closure panel substantially fills the open area of the partially-assembled casing. A backing layer is radially inward of, and attached to, the closure panel. The backing layer extends beyond a peripheral boundary of the closure panel, such that the backing layer at least partially overlaps one or more of the joined panels adjacent to the open area of the partially-assembled casing. A bladder is radially inward of, and attached to, the closure panel. The bladder includes a valve for introducing fluid into the ball. The valve extends through the backing layer and the closure panel. A backing patch may be attached either to the closure or the partially-assembled casing, and overlaps a portion of both.

A sport ball may include a casing that forms an exterior surface of the sport ball. The casing may incorporate a plurality of joined panels, including a closure panel. In addition, the ball may include a backing layer located radially inward of the closure panel, the backing layer extending beyond a peripheral boundary of the closure panel and at least partially overlapping with one or more panels adjacent to the closure panel. The backing layer may also include an opening located radially inward of the closure panel, the opening being smaller than the surface area of the closure panel. Also, the ball may include a bladder located radially inward of the backing layer, the bladder including a valve for introducing fluid into the ball, the valve extending through the opening and through the closure panel.