diff --git a/.github/workflows/phpunit.yml b/.github/workflows/phpunit.yml
index 837bf0be7..1c07954d0 100644
--- a/.github/workflows/phpunit.yml
+++ b/.github/workflows/phpunit.yml
@@ -236,7 +236,7 @@ jobs:
           
           REPO_ROOT="`pwd`"
           cd "$REPO_ROOT"/server/moodle
-          composer require --dev phpunit/phpunit
+          composer require --dev phpunit/phpunit ^9
 
           if [ ! -d "$REPO_ROOT/server/moodledata/phpunit" ]; then
             mkdir "$REPO_ROOT/server/moodledata/phpunit"