diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2dcc911f..688f105b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,6 +22,13 @@ jobs:
             os: ubuntu-latest
             toxenv: lint
 
+    env:
+      # Set TOXENV env var to tell tox which testenv (see tox.ini) to use
+      # NOTE: The Python 2.7 runner has two Python versions on the path (see
+      # setup-python below), so we tell tox explicitly to use the 'py27'
+      # testenv. For all other runners the toxenv configured above suffices.
+      TOXENV: ${{ matrix.python-version == '2.7' && 'py27' || matrix.toxenv }}
+
     runs-on: ${{ matrix.os }}
 
     steps:
@@ -33,6 +40,12 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
 
+      - name: Set up service Python 3.x (on 2.7 only)
+        uses: actions/setup-python@v2
+        if: ${{ matrix.python-version == 2.7 }}
+        with:
+          python-version: 3.x
+
       - name: Find pip cache dir
         id: pip-cache
         run: echo "::set-output name=dir::$(pip cache dir)"
@@ -52,8 +65,9 @@ jobs:
           python -m pip install --upgrade pip
           pip install --upgrade tox coveralls
 
-      - name: Run tox
-        run: tox -e ${{ matrix.toxenv }}
+      - name: Run tox (${{ env.TOXENV }})
+        # See TOXENV environment variable for the testenv to be executed here
+        run: tox
 
       - name: Publish on coveralls.io
         # TODO: Maybe make 'lint' a separate job instead of case handling here
diff --git a/tox.ini b/tox.ini
index a86fba4f..acf80441 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,6 +14,7 @@ skipsdist = true
 changedir = tests
 
 commands =
+    python --version
     coverage run aggregate_tests.py
     coverage report -m --fail-under 97