diff --git a/test/Microsoft.AspNet.Diagnostics.Tests/ElmMiddlewareTest.cs b/test/Microsoft.AspNet.Diagnostics.Tests/ElmMiddlewareTest.cs
index 14bfd4b35b..b3b69b5b4f 100644
--- a/test/Microsoft.AspNet.Diagnostics.Tests/ElmMiddlewareTest.cs
+++ b/test/Microsoft.AspNet.Diagnostics.Tests/ElmMiddlewareTest.cs
@@ -274,9 +274,9 @@ namespace Microsoft.AspNet.Diagnostics.Tests
         }
 
         [Theory]
-        [InlineData(null)]
         [InlineData("")]
-        public async Task UpdatesTraceIdentifier_IfNullOrEmpty(string requestId)
+        // Note that HttpRequestIdentifierFeature now provides a default TraceIdentifier and will never return null.
+        public async Task UpdatesTraceIdentifier_IfEmpty(string requestId)
         {
             var context = new DefaultHttpContext();
             var requestIdentifierFeature = new HttpRequestIdentifierFeature() { TraceIdentifier = requestId };