diff --git a/tests/hazmat/backends/test_openssl.py b/tests/hazmat/backends/test_openssl.py
index c2a4f54..0f2c80a 100644
--- a/tests/hazmat/backends/test_openssl.py
+++ b/tests/hazmat/backends/test_openssl.py
@@ -531,7 +531,7 @@
         )
 
         with pytest.raises(NotImplementedError):
-            builder.sign(backend, private_key, hashes.SHA1())
+            builder.sign(private_key, hashes.SHA1(), backend)
 
 
 class TestOpenSSLSerialisationWithOpenSSL(object):