diff --git a/resources/Materials/TestSuite/stdlib/upgrade/syntax_1_38.mtlx b/resources/Materials/TestSuite/stdlib/upgrade/syntax_1_38.mtlx
new file mode 100644
index 0000000000..21a465a1b9
--- /dev/null
+++ b/resources/Materials/TestSuite/stdlib/upgrade/syntax_1_38.mtlx
@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<materialx version="1.38">
+  <tiledimage name="N_tiledimage" type="vector3">
+    <input name="file" type="filename" value="resources/Images/mesh_wire_norm.png" />
+    <input name="uvtiling" type="vector2" value="8.0, 8.0" />
+  </tiledimage>
+  <normalmap name="N_normalmap" type="vector3" nodedef="ND_normalmap">
+    <input name="in" type="vector3" nodename="N_tiledimage" />
+  </normalmap>
+  <standard_surface name="N_surface" type="surfaceshader">
+    <input name="base_color" type="color3" value="1.0, 1.0, 1.0" />
+    <input name="specular_roughness" type="float" value="0" />
+    <input name="metalness" type="float" value="1" />
+    <input name="normal" type="vector3" nodename="N_normalmap" />
+  </standard_surface>
+  <surfacematerial name="N_material" type="material">
+    <input name="surfaceshader" type="surfaceshader" nodename="N_surface" />
+  </surfacematerial>
+</materialx>
diff --git a/source/MaterialXCore/Version.cpp b/source/MaterialXCore/Version.cpp
index a1a6e16d5b..a7cddd942d 100644
--- a/source/MaterialXCore/Version.cpp
+++ b/source/MaterialXCore/Version.cpp
@@ -1316,15 +1316,20 @@ void Document::upgradeVersion()
             }
             else if (nodeCategory == "normalmap")
             {
-                // ND_normalmap was renamed to ND_normalmap_float
+                // The nodedef for scalar normal maps was renamed.
+                const string ORIG_SCALAR_NORMALMAP_ND = "ND_normalmap";
+                const string NEW_SCALAR_NORMALMAP_ND = "ND_normalmap_float";
                 NodeDefPtr nodeDef = getShaderNodeDef(node);
                 InputPtr scaleInput = node->getInput("scale");
-                if ((nodeDef && nodeDef->getName() == "ND_normalmap") ||
-                    (scaleInput && scaleInput->getType() == "float"))
+                bool isScalarNormalMap = (nodeDef && nodeDef->getName() == ORIG_SCALAR_NORMALMAP_ND) ||
+                                         (node->getNodeDefString() == ORIG_SCALAR_NORMALMAP_ND) ||
+                                         (scaleInput && scaleInput->getType() == getTypeString<float>());
+                if (isScalarNormalMap)
                 {
-                    node->setNodeDefString("ND_normalmap_float");
+                    node->setNodeDefString(NEW_SCALAR_NORMALMAP_ND);
                 }
 
+                // The space input for normal maps was removed.
                 node->removeInput("space");
 
                 // If the normal or tangent inputs are set, the bitangent input should be normalize(cross(N, T))