diff --git a/reframe/core/meta.py b/reframe/core/meta.py
index 1d2aa75afc..4934d9a4da 100644
--- a/reframe/core/meta.py
+++ b/reframe/core/meta.py
@@ -433,7 +433,8 @@ def __call__(cls, *args, **kwargs):
         # the init phase
         varinfo = cls.get_variant_info(variant_num, recurse=True)
         for fname, finfo in varinfo['fixtures'].items():
-            if not isinstance(finfo, tuple):
+            fixt = cls.fixture_space[fname]
+            if fixt.action != 'join':
                 setattr(obj, fname, fixtures.FixtureProxy(finfo))
 
         obj.__init__(*args, **kwargs)
diff --git a/reframe/core/pipeline.py b/reframe/core/pipeline.py
index eb783a21bc..24ff6de1b7 100644
--- a/reframe/core/pipeline.py
+++ b/reframe/core/pipeline.py
@@ -1146,11 +1146,10 @@ def _format_params(cls, info, prefix=' %'):
                 name += f'{prefix}{p}={format_fn(v)}'
 
             for f, v in info['fixtures'].items():
-                if isinstance(v, tuple):
-                    # This is join fixture
+                fixt = cls.fixture_space[f]
+                if fixt.action == 'join':
                     continue
 
-                fixt = cls.fixture_space[f]
                 name += _format_params(fixt.cls, v, f'{prefix}{f}.')
 
                 # Append any variables set for the fixtures
diff --git a/unittests/test_fixtures.py b/unittests/test_fixtures.py
index f9160a5ac7..81431ddd5b 100644
--- a/unittests/test_fixtures.py
+++ b/unittests/test_fixtures.py
@@ -202,7 +202,6 @@ class FooB(rfm.RegressionTest):
 
     class Bar(rfm.RegressionTest):
         f = fixture(FooB, variables={'z': 5})
-        w = fixture(FooB, action='join')
 
         valid_systems = ['*']
         valid_prog_environs = ['*']
@@ -211,7 +210,6 @@ class Bar(rfm.RegressionTest):
         def early_access(self):
             assert self.f.foo.x == 1
             assert self.f.y == 2
-            assert self.w.y == 2
 
     Bar(variant_num=0)