diff --git a/src/NzbDrone.Core/DecisionEngine/Specifications/UpgradableSpecification.cs b/src/NzbDrone.Core/DecisionEngine/Specifications/UpgradableSpecification.cs
index a937d033c1..ed28983eb2 100644
--- a/src/NzbDrone.Core/DecisionEngine/Specifications/UpgradableSpecification.cs
+++ b/src/NzbDrone.Core/DecisionEngine/Specifications/UpgradableSpecification.cs
@@ -78,7 +78,12 @@ public bool IsUpgradable(QualityProfile profile, QualityModel currentQuality, Li
                 return false;
             }
 
-            _logger.Debug("New item has a better custom format score");
+            _logger.Debug("New item's custom formats [{0}] ({1}) improve on [{2}] ({3}), accepting",
+                newCustomFormats.ConcatToString(),
+                newFormatScore,
+                currentCustomFormats.ConcatToString(),
+                currentFormatScore);
+
             return true;
         }