diff --git a/src/tests/functional/requirements.txt b/src/tests/functional/requirements.txt
index f30cd14..97a5866 100644
--- a/src/tests/functional/requirements.txt
+++ b/src/tests/functional/requirements.txt
@@ -1,6 +1,6 @@
 flake8
 juju
 mock
-pytest
+pytest < 5.4.0  # pytest 5.4.0 deprecated `pytest.Function()` construction
 pytest-asyncio == 0.10.0 # https://github.com/pytest-dev/pytest-asyncio/issues/154
 requests