A sole structure of an article of footwear, the sole structure comprising: a first outer region at least partially disposed a first distance from a longitudinal axis (A14-A14) and having a first hardness; a second outer region at least partially disposed a second distance from the longitudinal axis (A14-A14) and having a second hardness that is greater than the first hardness; and a third outer region at least partially disposed between the first outer region and the second outer region a third distance from the longitudinal axis (A14-A14) and having a third hardness that is greater than the first hardness and less than the second hardness, wherein the second distance is greater than the first distance, and the third distance is greater than the first distance and less than the second distance, wherein the sole structure includes: an outsole including the second outer region and the third outer region and defining a first passage; and a midsole including a first outer pad disposed within the first passage, the first outer pad including the first outer region, and wherein the outsole includes: an outsole base layer including the second outer region and at least one opening (102, 104); and an outsole insert layer including the third outer region and at least one opening (106, 108, 110), wherein the at least one opening (102, 104) of the outsole base layer is aligned with the at least one opening (106, 108, 110) of the outsole insert layer, and wherein the at least one opening (102, 104) of the outsole base layer and the at least one opening of the outsole insert layer are sized for receiving and permitting passage of the first outer pad. a first outer region at least partially disposed a first distance from a longitudinal axis (A14-A14) and having a first hardness; a second outer region at least partially disposed a second distance from the longitudinal axis (A14-A14) and having a second hardness that is greater than the first hardness; and a third outer region at least partially disposed between the first outer region and the second outer region a third distance from the longitudinal axis (A14-A14) and having a third hardness that is greater than the first hardness and less than the second hardness, wherein the second distance is greater than the first distance, and the third distance is greater than the first distance and less than the second distance, wherein the sole structure includes: an outsole including the second outer region and the third outer region and defining a first passage; and a midsole including a first outer pad disposed within the first passage, the first outer pad including the first outer region, and an outsole including the second outer region and the third outer region and defining a first passage; and a midsole including a first outer pad disposed within the first passage, the first outer pad including the first outer region, and wherein the outsole includes: an outsole base layer including the second outer region and at least one opening (102, 104); and an outsole insert layer including the third outer region and at least one opening (106, 108, 110), wherein the at least one opening (102, 104) of the outsole base layer is aligned with the at least one opening (106, 108, 110) of the outsole insert layer, and wherein the at least one opening (102, 104) of the outsole base layer and the at least one opening of the outsole insert layer are sized for receiving and permitting passage of the first outer pad. an outsole base layer including the second outer region and at least one opening (102, 104); and an outsole insert layer including the third outer region and at least one opening (106, 108, 110), wherein the at least one opening (102, 104) of the outsole base layer is aligned with the at least one opening (106, 108, 110) of the outsole insert layer, and wherein the at least one opening (102, 104) of the outsole base layer and the at least one opening of the outsole insert layer are sized for receiving and permitting passage of the first outer pad.