diff --git a/src/Microsoft.AspNetCore.Mvc.Core/Formatters/TextOutputFormatter.cs b/src/Microsoft.AspNetCore.Mvc.Core/Formatters/TextOutputFormatter.cs
index fb2a07a1fb..c30901da00 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/Formatters/TextOutputFormatter.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/Formatters/TextOutputFormatter.cs
@@ -173,7 +173,7 @@ namespace Microsoft.AspNetCore.Mvc.Formatters
                 return result;
             }
 
-            return null;
+            return Array.Empty<StringWithQualityHeaderValue>();
         }
 
         private string GetMediaTypeWithCharset(string mediaType, Encoding encoding)