File photo. EASTERN IDAHO – Preston defeated Marsh Valley in the South East Idaho Conference tournament final on Saturday, but both teams will advance to next week’s 4A state tournament. Here’s a recap of Saturday’s softball postseason results. Preston 12, Marsh Valley 1 Preston was the No. 1 seed, but No. 5 Marsh Valley worked its way back through the bracket to earn the berth in the final and a berth in the state tournament. Preston (22-2) led…