diff --git a/src/pocketmine/ThreadManager.php b/src/pocketmine/ThreadManager.php
index b84f6509a..4d232c3fa 100644
--- a/src/pocketmine/ThreadManager.php
+++ b/src/pocketmine/ThreadManager.php
@@ -52,7 +52,7 @@ class ThreadManager extends \Volatile{
 	 */
 	public function add($thread){
 		if($thread instanceof Thread or $thread instanceof Worker){
-			$this->{spl_object_hash($thread)} = $thread;
+			$this[spl_object_hash($thread)] = $thread;
 		}
 	}
 
@@ -63,7 +63,7 @@ class ThreadManager extends \Volatile{
 	 */
 	public function remove($thread){
 		if($thread instanceof Thread or $thread instanceof Worker){
-			unset($this->{spl_object_hash($thread)});
+			unset($this[spl_object_hash($thread)]);
 		}
 	}