diff --git a/tests/Doctrine/Tests/ORM/Functional/Ticket/DDC6613Test.php b/tests/Doctrine/Tests/ORM/Functional/Ticket/DDC6613Test.php
index 11b8f5111..30e4f5276 100644
--- a/tests/Doctrine/Tests/ORM/Functional/Ticket/DDC6613Test.php
+++ b/tests/Doctrine/Tests/ORM/Functional/Ticket/DDC6613Test.php
@@ -16,6 +16,7 @@ use Doctrine\ORM\Mapping\Entity;
 use Doctrine\ORM\Mapping\Id;
 use Doctrine\ORM\Mapping\GeneratedValue;
 use Doctrine\ORM\Mapping\ManyToOne;
+use Doctrine\ORM\PersistentCollection;
 use Doctrine\ORM\Proxy\Proxy;
 use Doctrine\Tests\Models\DDC6613\Phone;
 use Doctrine\Tests\Models\DDC6613\User;
@@ -31,8 +32,8 @@ class DDC6613Test extends \Doctrine\Tests\OrmFunctionalTestCase
         try {
             $this->setUpEntitySchema(
                 [
-                    Phone::class,
-                    User::class
+                    DDC6613Phone::class,
+                    DDC6613User::class
                 ]
             );
         } catch (SchemaException $e) {
@@ -41,8 +42,7 @@ class DDC6613Test extends \Doctrine\Tests\OrmFunctionalTestCase
 
     public function testFail()
     {
-        $user = new User();
-        $user->id = 1;
+        $user = new DDC6613User();
         $this->_em->persist($user);
         $this->_em->flush();
 
@@ -50,18 +50,78 @@ class DDC6613Test extends \Doctrine\Tests\OrmFunctionalTestCase
 
         /** @var User $user */
         $user = $this->_em->find(User::class, 1);
-        $phone1 = new Phone();
-        $phone1->id = 1;
+        $phone1 = new DDC6613Phone();
+        $phones = $user->phones;
         $user->phones->add($phone1);
         $this->_em->persist($phone1);
         $this->_em->flush();
 
-        $phone2 = new Phone();
-        $phone2->id = 2;
+        $phone2 = new DDC6613Phone();
         $user->phones->add($phone2);
         $this->_em->persist($phone2);
-        $user->phones->toArray();
+
+        /* @var $phones PersistentCollection */
+//        $phones = $user->phones;
+
+        self::assertInstanceOf(PersistentCollection::class, $phones);
+        self::assertFalse($phones->isInitialized());
+
+        $phones->initialize();
+
+        self::assertTrue($phones->isInitialized());
+        self::assertCount(2, $phones);
+
         $this->_em->flush();
+
+        self::assertFalse($phones->isDirty());
+        self::assertTrue($phones->isInitialized());
+        self::assertCount(2, $user->phones);
     }
 
+}
+
+/**
+ * @Entity
+ * @Table(name="ddc6613_user")
+ */
+class DDC6613User
+{
+    /**
+     * @Id
+     * @GeneratedValue(strategy="NONE")
+     * @Column(type="string")
+     */
+    private $id;
+
+    /**
+     * @ManyToMany(targetEntity="Phone", fetch="LAZY", cascade={"remove", "detach"})
+     */
+    public $phones;
+
+    public function __construct()
+    {
+        $this->id     = uniqid('user', true);
+        $this->phones = new ArrayCollection();
+    }
+
+
+}
+
+/**
+ * @Table(name="ddc6613_phone")
+ */
+class DDC6613Phone
+{
+
+    /**
+     * @Id
+     * @GeneratedValue(strategy="NONE")
+     * @Column(type="integer")
+     */
+    public $id;
+
+    public function __construct()
+    {
+        $this->id = uniqid('phone', true);
+    }
 }
\ No newline at end of file