diff --git a/PKHeX.Core/Saves/Substructures/Gen4/SAV4BlockDetection.cs b/PKHeX.Core/Saves/Substructures/Gen4/SAV4BlockDetection.cs
index c186dc8d0..eaf20b9d1 100644
--- a/PKHeX.Core/Saves/Substructures/Gen4/SAV4BlockDetection.cs
+++ b/PKHeX.Core/Saves/Substructures/Gen4/SAV4BlockDetection.cs
@@ -35,10 +35,10 @@ public static int CompareFooters(byte[] data, int offset1, int offset2)
 
         private static int CompareCounters(uint counter1, uint counter2)
         {
-            // Uninitialized
-            if (counter1 == uint.MaxValue && counter2 == 0)
+            // Uninitialized -- only continue if a rollover case (humanly impossible)
+            if (counter1 == uint.MaxValue && counter2 != uint.MaxValue - 1)
                 return Second;
-            if (counter1 == 0 && counter2 == uint.MaxValue)
+            if (counter2 == uint.MaxValue && counter1 != uint.MaxValue - 1)
                 return First;
 
             // Different