COACHING Auburn had a bit of a brain drain on the defensive side of the coaching staff, losing co-defensive coordinator Charles Kelly to become head coach at Jacksonville State and linebackers coach Josh Aldridge to become defensive coordinator at East Carolina. The replacement hires – TJ Rushing for safeties and Roc Bellantoni for edges – are nobodies, they don’t do anything for me. This is a slight negative, but probably not a meaningful one. OFFENSE Five new starters will take the field for A…