And yet, in this rebuild under Coach Lincoln Riley that culminated in a purge-the-demons Holiday Bowl victory over Louisville on Wednesday night, no Trojan has been more vital. No Trojan has been more central to the heart of the program, the culture that has been spoken of but never consistently materialized, until a group of second-stringers and veterans that truly wanted to be there came into Petco Park and knocked off 15th-ranked Louisville, 42-28.