diff --git a/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit b/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit
index a2747f3be2..ae4c818aa3 100755
--- a/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit
+++ b/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit
@@ -60,7 +60,8 @@ if (!file_exists("$PHPUNIT_DIR/phpunit-$PHPUNIT_VERSION/phpunit") || md5_file(__
     $zip->extractTo(getcwd());
     $zip->close();
     chdir("phpunit-$PHPUNIT_VERSION");
-    passthru("$COMPOSER remove --no-update ".(getenv('SYMFONY_PHPUNIT_REMOVE') ?: 'phpspec/prophecy symfony/yaml'));
+    $SYMFONY_PHPUNIT_REMOVE = getenv('SYMFONY_PHPUNIT_REMOVE');
+    passthru("$COMPOSER remove --no-update ".('' === $SYMFONY_PHPUNIT_REMOVE ?: 'phpspec/prophecy symfony/yaml'));
     if (5.1 <= $PHPUNIT_VERSION && $PHPUNIT_VERSION < 5.4) {
         passthru("$COMPOSER require --no-update phpunit/phpunit-mock-objects \"~3.1.0\"");
     }