diff --git a/src/Microsoft.AspNetCore.Mvc.Core/Formatters/MediaTypeCollection.cs b/src/Microsoft.AspNetCore.Mvc.Core/Formatters/MediaTypeCollection.cs
index 065bbde7cd..5fa822c59a 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/Formatters/MediaTypeCollection.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/Formatters/MediaTypeCollection.cs
@@ -30,7 +30,7 @@ public void Add(MediaTypeHeaderValue item)
                 throw new ArgumentNullException(nameof(item));
             }
 
-            Add(item?.ToString());
+            Add(item.ToString());
         }
 
         /// <summary>