diff --git a/test/runner/completion/docker.txt b/test/runner/completion/docker.txt
index b466eca1a1..b4e8ed79cb 100644
--- a/test/runner/completion/docker.txt
+++ b/test/runner/completion/docker.txt
@@ -1,11 +1,11 @@
-default name=quay.io/ansible/default-test-container:1.2.0
+default name=quay.io/ansible/default-test-container:1.2.0 python=3
 centos6 name=quay.io/ansible/centos6-test-container:1.4.0 seccomp=unconfined
 centos7 name=quay.io/ansible/centos7-test-container:1.4.0 seccomp=unconfined
 fedora24 name=quay.io/ansible/fedora24-test-container:1.4.0 seccomp=unconfined
 fedora25 name=quay.io/ansible/fedora25-test-container:1.4.0 seccomp=unconfined
-fedora26py3 name=quay.io/ansible/fedora26py3-test-container:1.4.0
-fedora27py3 name=quay.io/ansible/fedora27py3-test-container:1.4.0
+fedora26py3 name=quay.io/ansible/fedora26py3-test-container:1.4.0 python=3
+fedora27py3 name=quay.io/ansible/fedora27py3-test-container:1.4.0 python=3
 opensuse42.3 name=quay.io/ansible/opensuse42.3-test-container:1.4.0 seccomp=unconfined
 ubuntu1404 name=quay.io/ansible/ubuntu1404-test-container:1.4.0 seccomp=unconfined
 ubuntu1604 name=quay.io/ansible/ubuntu1604-test-container:1.4.0 seccomp=unconfined
-ubuntu1604py3 name=quay.io/ansible/ubuntu1604py3-test-container:1.4.0 seccomp=unconfined
+ubuntu1604py3 name=quay.io/ansible/ubuntu1604py3-test-container:1.4.0 seccomp=unconfined python=3
diff --git a/test/runner/lib/executor.py b/test/runner/lib/executor.py
index 5fcca6cbe9..ac8bcd4bdb 100644
--- a/test/runner/lib/executor.py
+++ b/test/runner/lib/executor.py
@@ -52,6 +52,7 @@ from lib.util import (
     get_available_port,
     generate_pip_command,
     find_python,
+    get_docker_completion,
 )
 
 from lib.docker_util import (
@@ -1457,15 +1458,9 @@ def get_integration_docker_filter(args, targets):
             display.warning('Excluding tests marked "%s" which require --docker-privileged to run under docker: %s'
                             % (skip.rstrip('/'), ', '.join(skipped)))
 
-    docker_image = args.docker.split('@')[0]  # strip SHA for proper tag comparison
-
     python_version = 2  # images are expected to default to python 2 unless otherwise specified
 
-    if docker_image.endswith('py3'):
-        python_version = 3  # docker images ending in 'py3' are expected to default to python 3
-
-    if docker_image.endswith(':default'):
-        python_version = 3  # docker images tagged 'default' are expected to default to python 3
+    python_version = int(get_docker_completion().get(args.docker_raw).get('python', str(python_version)))
 
     if args.python:  # specifying a numeric --python option overrides the default python
         if args.python.startswith('3'):