2 files changed, 2 insertions, 4 deletions
diff --git a/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs b/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs
index 8cfdb779..6083f171 100644
--- a/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs
+++ b/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs
@@ -94,7 +94,7 @@ namespace Google.Protobuf.Reflection
         /// <summary>
         /// The json_name option of the descriptor's target.
         /// </summary>
-        public string JsonName { get { return proto.JsonName; } }
+        public string JsonName { get { return proto.JsonName == "" ? JsonFormatter.ToCamelCase(proto.Name) : proto.JsonName; } }
 
         internal FieldDescriptorProto Proto { get { return proto; } }
 
diff --git a/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs b/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs
index 63f168ca..f5a835e5 100644
--- a/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs
+++ b/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs
@@ -102,10 +102,8 @@ namespace Google.Protobuf.Reflection
             var map = new Dictionary<string, FieldDescriptor>();
             foreach (var field in fields)
             {
-                map[JsonFormatter.ToCamelCase(field.Name)] = field;
                 map[field.Name] = field;
-                if (!string.IsNullOrEmpty(field.JsonName))
-                    map[field.JsonName] = field;
+                map[field.JsonName] = field;
             }
             return new ReadOnlyDictionary<string, FieldDescriptor>(map);
         }