diff --git a/jsonargparse/_typehints.py b/jsonargparse/_typehints.py
index 445026c3..22204f82 100644
--- a/jsonargparse/_typehints.py
+++ b/jsonargparse/_typehints.py
@@ -396,6 +396,8 @@ def parse_argv_item(arg_string):
         if typehint:
             if parse_optional_num_return == 4:
                 return action, arg_base, sep, explicit_arg
+            elif parse_optional_num_return == 1:
+                return [(action, arg_base, sep, explicit_arg)]
             return action, arg_base, explicit_arg
         return None