A method of making a tread assembly (502; 1102; 2202) for an outsole of an article of footwear, comprising the steps of: placing a matrix lining (202; 802; 1502) between a molding base (108; 726; 1308) and a first side (191; 780; 1381) of a central mold (104; 704; 1304); placing a rubber block (302; 902, 904; 1602) between a molding press; 702; 1302) and a second side (190; 781; 1380) of the central mold (104; 704; 1304); and compressing the rubber block (302; 902, 904; 1602) between the molding press (102; 702; 1302) and the second side (190; 781; 1380) of the central mold (104; 704; 1304), so that the rubber block (302; 902, 904; 1602) liquefies and flows through at least one injection cavity (112, 113; 790, 791; 1312, 1313) disposed in the central mold (104; 704; 1304) and into at least one lug cavity (114, 115; 734, 736; 1314, 1315) disposed in the central mold (104; 704; 1304); wherein the lug cavity (114, 115; 734, 736; 1314, 1315) is disposed proximate the matrix lining, and the lug cavity (114, 115; 734, 736; 1314, 1315) includes a lug cavity rim (402, 404; 1002, 1004; 1702, 1704) that extends around the entire outer periphery of the lug cavity (114, 115; 734, 736; 1314, 1315), characterized in that the method further includes the steps of: pressing the matrix lining (202; 802; 1502) by movement of the central mold (104, 704; 1304) to fill a lining recess (116, 117, 119; 740, 742, 744; 1316, 1317, 1319) of the central mold (104, 704, 1304) on the outer circumference of the lug cavity rim (402, 404; 1002, 1004; 1702, 1704); and pressing the lug cavity rim (402, 404; 1002, 1004; 1702, 1704) in contact with the matrix lining (202; 802; 1502) so that viscous rubber material flowing into the lug cavity (114, 115; 734, 736; 1314, 1315) is contained by the lug cavity rim (402, 404; 1002, 1004; 1702, 1704). placing a matrix lining (202; 802; 1502) between a molding base (108; 726; 1308) and a first side (191; 780; 1381) of a central mold (104; 704; 1304); placing a rubber block (302; 902, 904; 1602) between a molding press; 702; 1302) and a second side (190; 781; 1380) of the central mold (104; 704; 1304); and compressing the rubber block (302; 902, 904; 1602) between the molding press (102; 702; 1302) and the second side (190; 781; 1380) of the central mold (104; 704; 1304), so that the rubber block (302; 902, 904; 1602) liquefies and flows through at least one injection cavity (112, 113; 790, 791; 1312, 1313) disposed in the central mold (104; 704; 1304) and into at least one lug cavity (114, 115; 734, 736; 1314, 1315) disposed in the central mold (104; 704; 1304); wherein the lug cavity (114, 115; 734, 736; 1314, 1315) is disposed proximate the matrix lining, and the lug cavity (114, 115; 734, 736; 1314, 1315) includes a lug cavity rim (402, 404; 1002, 1004; 1702, 1704) that extends around the entire outer periphery of the lug cavity (114, 115; 734, 736; 1314, 1315), characterized in that the method further includes the steps of: pressing the matrix lining (202; 802; 1502) by movement of the central mold (104, 704; 1304) to fill a lining recess (116, 117, 119; 740, 742, 744; 1316, 1317, 1319) of the central mold (104, 704, 1304) on the outer circumference of the lug cavity rim (402, 404; 1002, 1004; 1702, 1704); and pressing the lug cavity rim (402, 404; 1002, 1004; 1702, 1704) in contact with the matrix lining (202; 802; 1502) so that viscous rubber material flowing into the lug cavity (114, 115; 734, 736; 1314, 1315) is contained by the lug cavity rim (402, 404; 1002, 1004; 1702, 1704). pressing the matrix lining (202; 802; 1502) by movement of the central mold (104, 704; 1304) to fill a lining recess (116, 117, 119; 740, 742, 744; 1316, 1317, 1319) of the central mold (104, 704, 1304) on the outer circumference of the lug cavity rim (402, 404; 1002, 1004; 1702, 1704); and pressing the lug cavity rim (402, 404; 1002, 1004; 1702, 1704) in contact with the matrix lining (202; 802; 1502) so that viscous rubber material flowing into the lug cavity (114, 115; 734, 736; 1314, 1315) is contained by the lug cavity rim (402, 404; 1002, 1004; 1702, 1704).