Like Wirtz, Berbatov is a former Bayer Leverkusen star.
And he said on the Rio Ferdinand podcast: "I love him. He’s a fantastic player. He will be unbelievable, trust me.
"Hopefully, he will be patient. Hopefully, he’ll have good people around him, agent, family, whatever. Hopefully, the coach sees his quality like everybody sees him.
"I’m sure that everybody sees his quality, and they’ll give him that time that he needs to fit into the team. And I guarantee you, he’s going to be a success.
"The way he sees football, how he looks for the space, how he knows how to position himself, the touches on the ball, the improvisation, the eye for the pass and for the goals.
"Of course, someone can argue that his physique is not that great for the Premier League. But then you can easily see the great players of his position, like Modric, also the same build. Modric. F***ing monster. It’s unbelievable.
"So give him time. I think he’s going to be unbelievable for Liverpool."