diff --git a/tox.ini b/tox.ini
index d36ddde4..32cafdef 100644
--- a/tox.ini
+++ b/tox.ini
@@ -49,7 +49,7 @@ commands =
     sh -c "which python"
     python -V
     coverage --version
-    asyncio: coverage run {envbindir}/py.test autobahn/
+    asyncio: coverage run {envbindir}/py.test {envsitepackagesdir}/autobahn/
     tw121,tw132,tw155,twtrunk: coverage run {envbindir}/trial autobahn
     coverage report