diff --git a/game-app/game-core/src/main/java/games/strategy/triplea/ai/pro/util/ProSortMoveOptionsUtils.java b/game-app/game-core/src/main/java/games/strategy/triplea/ai/pro/util/ProSortMoveOptionsUtils.java
index 63c4cb5b99..9b9dbf3570 100644
--- a/game-app/game-core/src/main/java/games/strategy/triplea/ai/pro/util/ProSortMoveOptionsUtils.java
+++ b/game-app/game-core/src/main/java/games/strategy/triplea/ai/pro/util/ProSortMoveOptionsUtils.java
@@ -1,5 +1,6 @@
 package games.strategy.triplea.ai.pro.util;
 
+import com.google.common.base.Preconditions;
 import games.strategy.engine.data.GameData;
 import games.strategy.engine.data.GamePlayer;
 import games.strategy.engine.data.GameState;
@@ -230,10 +231,12 @@ private static double calculateAttackEfficiency(
         minPower = powerDifference;
       }
     }
-
     if (unit.getUnitAttachment().getIsAir()) {
       minPower *= 10;
     }
-    return (double) minPower / proData.getUnitValue(unit.getType());
+    final double unitValue = proData.getUnitValue(unit.getType());
+    final double result = unitValue == 0.0 ? 0.0 : (double) minPower / unitValue;
+    Preconditions.checkState(Double.isFinite(result));
+    return result;
   }
 }