diff --git a/acme/acme/client.py b/acme/acme/client.py
index 877560767..6c8d5cbbc 100644
--- a/acme/acme/client.py
+++ b/acme/acme/client.py
@@ -123,42 +123,6 @@ class ClientBase(object):  # pylint: disable=too-many-instance-attributes
             raise errors.UnexpectedUpdate(authzr)
         return authzr
 
-    def request_challenges(self, identifier, new_authzr_uri=None):
-        """Request challenges.
-
-        :param .messages.Identifier identifier: Identifier to be challenged.
-        :param str new_authzr_uri: Deprecated. Do not use.
-
-        :returns: Authorization Resource.
-        :rtype: `.AuthorizationResource`
-
-        """
-        if new_authzr_uri is not None:
-            logger.debug("request_challenges with new_authzr_uri deprecated.")
-        new_authz = messages.NewAuthorization(identifier=identifier)
-        response = self.net.post(self.directory.new_authz, new_authz)
-        # TODO: handle errors
-        assert response.status_code == http_client.CREATED
-        return self._authzr_from_response(response, identifier)
-
-    def request_domain_challenges(self, domain, new_authzr_uri=None):
-        """Request challenges for domain names.
-
-        This is simply a convenience function that wraps around
-        `request_challenges`, but works with domain names instead of
-        generic identifiers. See ``request_challenges`` for more
-        documentation.
-
-        :param str domain: Domain name to be challenged.
-        :param str new_authzr_uri: Deprecated. Do not use.
-
-        :returns: Authorization Resource.
-        :rtype: `.AuthorizationResource`
-
-        """
-        return self.request_challenges(messages.Identifier(
-            typ=messages.IDENTIFIER_FQDN, value=domain), new_authzr_uri)
-
     def answer_challenge(self, challb, response):
         """Answer challenge.