diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index f32ce64629..71005490f3 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -1587,7 +1587,7 @@ class DurationField(Field):
     empty_strings_allowed = False
     default_error_messages = {
         'invalid': _("'%(value)s' value has an invalid format. It must be in "
-                     "[DD] [HH:[MM:]]ss[.uuuuuu] format.")
+                     "[DD] [[HH:]MM:]ss[.uuuuuu] format.")
     }
     description = _("Duration")
 
diff --git a/tests/model_fields/test_durationfield.py b/tests/model_fields/test_durationfield.py
index b73994f86a..f1c82ab8bd 100644
--- a/tests/model_fields/test_durationfield.py
+++ b/tests/model_fields/test_durationfield.py
@@ -75,7 +75,7 @@ class TestValidation(SimpleTestCase):
         self.assertEqual(
             cm.exception.message % cm.exception.params,
             "'not a datetime' value has an invalid format. "
-            "It must be in [DD] [HH:[MM:]]ss[.uuuuuu] format."
+            "It must be in [DD] [[HH:]MM:]ss[.uuuuuu] format."
         )