Wrong way to add a Doctrine2 relation

OneToManyFixture1.php

<?php

namespace Acme\DemoBundle\DataFixtures\ORM;

use Doctrine\Common\Persistence\ObjectManager;
use Doctrine\Common\DataFixtures\FixtureInterface;

use Acme\DemoBundle\Entity\Team;
use Acme\DemoBundle\Entity\Player;

class LoadDemoDataIO implements FixtureInterface
{
    public function load(ObjectManager $manager)
    {
        
        $players_source = array(
            array("name" => "Diego Armando Maradona"),
            array("name" => "Hristo Stoičkov"),
            array("name" => "Lev Yashin")            
        );
        
        $_team = new Team();
        $_team->setName("Dream team A");
        
        foreach ($players_source as $player_data) {
            
            $_player = new Player();
            $_player->setName($player_data['name']);
            $_team->addPlayer($_player);
            
        }
        
        $manager->persist($_player);
        $manager->flush();
            
    }
            
}