diff --git a/django/forms/fields.py b/django/forms/fields.py
index e2e712f0c1..16c9218549 100644
--- a/django/forms/fields.py
+++ b/django/forms/fields.py
@@ -581,14 +581,23 @@ class URLField(CharField):
 
     def to_python(self, value):
         if value:
-            if '://' not in value:
-                # If no URL scheme given, assume http://
-                value = u'http://%s' % value
             url_fields = list(urlparse.urlsplit(value))
+            if not url_fields[0]:
+                # If no URL scheme given, assume http://
+                url_fields[0] = 'http'
+            if not url_fields[1]:
+                # Assume that if no domain is provided, that the path segment
+                # contains the domain. 
+                url_fields[1] = url_fields[2]
+                url_fields[2] = ''
+                # Rebuild the url_fields list, since the domain segment may now
+                # contain the path too.
+                value = urlparse.urlunsplit(url_fields)
+                url_fields = list(urlparse.urlsplit(value))
             if not url_fields[2]:
                 # the path portion may need to be added before query params
                 url_fields[2] = '/'
-                value = urlparse.urlunsplit(url_fields)
+            value = urlparse.urlunsplit(url_fields)
         return super(URLField, self).to_python(value)
 
 class BooleanField(Field):
diff --git a/tests/regressiontests/forms/tests/fields.py b/tests/regressiontests/forms/tests/fields.py
index adf4c6e796..bc549a9848 100644
--- a/tests/regressiontests/forms/tests/fields.py
+++ b/tests/regressiontests/forms/tests/fields.py
@@ -495,6 +495,7 @@ class FieldsTests(TestCase):
         self.assertRaisesErrorWithMessage(ValidationError, "[u'Enter a valid URL.']", f.clean, 'http://inv-.-alid.com')
         self.assertEqual(u'http://valid-----hyphens.com/', f.clean('http://valid-----hyphens.com'))
         self.assertEqual(u'http://some.idn.xyz\xe4\xf6\xfc\xdfabc.domain.com:123/blah', f.clean('http://some.idn.xyzäöüßabc.domain.com:123/blah'))
+        self.assertEqual(u'http://www.example.com/s/http://code.djangoproject.com/ticket/13804', f.clean('www.example.com/s/http://code.djangoproject.com/ticket/13804'))
 
     def test_url_regex_ticket11198(self):
         f = URLField()