Steve Fisher has retired. The legendary San Diego State men’s basketball coach informed his staff, players and university President Elliot Hirshman of his decision Monday, the Union-Tribune has learned. A news conference has been scheduled for Tuesday afternoon to make the announcement and formally introduce Brian Dutcher, his longtime assistant and “head coach in waiting” since 2011, as his replacement. Mark Fisher, his son, is expected to remain with the program as a special assistant. Fisher, Dutcher and other SDSU officials were unavailable or declined immediate comment.