diff --git a/core/Update/UpdateManager.php b/core/Update/UpdateManager.php
index 185bc265..301ea22e 100644
--- a/core/Update/UpdateManager.php
+++ b/core/Update/UpdateManager.php
@@ -37,15 +37,6 @@ class UpdateManager implements CallbackListener, CommandListener, TimerListener
 	const SETTING_PERMISSION_UPDATECHECK = 'Check Core Update';
 	const BUILD_DATE_FILE_NAME           = 'build_date.txt';
 
-	/*
-	 * Public properties
-	 */
-	/** @var PluginUpdateManager $pluginUpdateManager
-	 * @deprecated
-	 * @see getPluginUpdateManager()
-	 */
-	public $pluginUpdateManager = null;
-
 	/*
 	 * Private properties
 	 */
@@ -55,6 +46,9 @@ class UpdateManager implements CallbackListener, CommandListener, TimerListener
 	/** @var UpdateData $coreUpdateData */
 	private $coreUpdateData = null;
 
+	/** @var PluginUpdateManager $pluginUpdateManager	 */
+	private $pluginUpdateManager = null;
+
 	/**
 	 * Construct a new update manager instance
 	 *