diff --git a/dotnet/targets/Microsoft.Sdk.R2R.targets b/dotnet/targets/Microsoft.Sdk.R2R.targets
index 5db954f9fd4..0ea9c5ed1fc 100644
--- a/dotnet/targets/Microsoft.Sdk.R2R.targets
+++ b/dotnet/targets/Microsoft.Sdk.R2R.targets
@@ -115,8 +115,8 @@
 
 
 	<!--
-		Exclude user assemblies from R2R composite so they run interpreted for debugging.
-		User assembly is defined as anything not coming from a NuGet package.
+		Restrict R2R composite input to System.Private.CoreLib so all other framework,
+		MAUI, and NuGet assemblies run interpreted for inner-loop debug builds.
 	-->
 	<Target Name="_SelectR2RAssemblies"
 			Condition="'$(FilterReadyToRunAssemblies)' == 'true' And '$(RuntimeIdentifiers)' == ''"
@@ -125,7 +125,7 @@
 			<_ResolvedAssembliesToPublish Include="@(ResolvedFileToPublish)" Condition="'%(Extension)' == '.dll' And '%(ResolvedFileToPublish.Culture)' == '' And '%(ResolvedFileToPublish.DestinationSubDirectory)' == ''" />
 			<_NonUserAssemblies
 				Include="@(_ResolvedAssembliesToPublish)"
-				Condition="'%(_ResolvedAssembliesToPublish.NuGetPackageId)' != ''" />
+				Condition="'%(_ResolvedAssembliesToPublish.NuGetPackageId)' != '' And '%(Filename)' == 'System.Private.CoreLib'" />
 			<_UserAssemblies Include="@(_ResolvedAssembliesToPublish)" Exclude="@(_NonUserAssemblies)" />
 			<PublishReadyToRunExclude Include="@(_UserAssemblies -> '%(Filename)%(Extension)')" />
 		</ItemGroup>