diff --git a/Extensions/Xtensive.Orm.Tracking/Internals/TrackingItem.cs b/Extensions/Xtensive.Orm.Tracking/Internals/TrackingItem.cs
index 8de53feee..4a580958e 100644
--- a/Extensions/Xtensive.Orm.Tracking/Internals/TrackingItem.cs
+++ b/Extensions/Xtensive.Orm.Tracking/Internals/TrackingItem.cs
@@ -37,15 +37,17 @@ public void MergeWith(ITrackingItem source)
         return;
       }
 
-      ArgumentNullException.ThrowIfNull(source.RawData);
-
       if (State == TrackingItemState.Created && source.State == TrackingItemState.Changed) {
+        ArgumentNullException.ThrowIfNull(source.RawData);
         State = TrackingItemState.Created;
         MergeWith(source.RawData.Difference);
         return;
       }
 
-      MergeWith(source.RawData.Difference);
+      if (source.RawData is not null) {
+        MergeWith(source.RawData.Difference);
+      }
+
       State = source.State;
     }
 
diff --git a/Version.props b/Version.props
index de5bbf360..1e4d3f310 100644
--- a/Version.props
+++ b/Version.props
@@ -2,7 +2,7 @@
 <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
 
 <PropertyGroup>
-    <DoVersion>7.2.172</DoVersion>
+    <DoVersion>7.2.173</DoVersion>
     <DoVersionSuffix>servicetitan</DoVersionSuffix>
 </PropertyGroup>