The Louisville Cardinals and the Kentucky Wildcats square off Saturday at Papa John's Cardinal Stadium as the college football season begins for both schools.It's a rebuilding season for U of L under new coach Charlie Strong, as the Cards try to rebound from three straight losing seasons.Strong says he has a simple message for his players heading into the opener."I just said play with passion, play with energy. Just play with passion and play with energy guys, and just play every play. Every play, just play every play and we'll see what happens, but we're playing a really good, outstanding football team," Strong said this week.UK also opens its season with a new coach, Joker Phillips, who was a top assistant to Rich Brooks in Lexington. Brooks retired after last season.Saturday's kickoff is 3:30pm. The game is sold out. UK has won the last three contests.