diff --git a/runners/phpunit-core/before_script.sh b/runners/phpunit-core/before_script.sh
index 4801f8f..53f74f7 100755
--- a/runners/phpunit-core/before_script.sh
+++ b/runners/phpunit-core/before_script.sh
@@ -6,5 +6,8 @@ set -e $DRUPAL_TI_DEBUG
 # Ensure the right Drupal version is downloaded.
 drupal_ti_ensure_drupal
 
+# Change directory to Drupal core directory.
+cd drupal
+
 # Ensure the module is linked into the code base.
 drupal_ti_ensure_module_linked