Bumper Bundesliga refresher course

Havertz, 20, has long been considered a future pillar of German football, having broken into the Leverkusen starting XI as a 17-year-old, smashing numerous records in the process.

The midfielder appears to be outgrowing Leverkusen and has been identified as a reported target for many of the world's biggest clubs, including Bayern.

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Leverkusen are said to be holding out for at least €100million for the Germany international, who is contracted to the club until 2022, but Ballack – who left Die Werkself for Bayern in 2002 – had a word of caution for Havertz.

"Players with his quality are in demand everywhere, but I think he's in good hands in Leverkusen," the former midfielder told SportBild.

"The general conditions there are perfect for top young players and their further development. Leverkusen play attractive football, the training opportunities are very good. Leverkusen also offers a cautious environment.

"As a player [at Leverkusen] you can sometimes make mistakes without being the focus of criticism - you should appreciate that.

"Of course, a player like Havertz would also like to play in the Champions League, so it would be important for Leverkusen to qualify."

Ballack does not doubt Havertz's ability. On the contrary, he considers the 20-year-old to be lacking very little from his game.

But he feels a player must be ready to make the step up, as Bayern is a more demanding and challenging place to play.

"As a footballer he'd bring everything with him," he said. "If we talk about Bayern, if you want to take the next step as a player, you also have to be prepared for such a challenge in order to survive in such a robust environment.

"That will really weigh up his surroundings – [determine] when the right time has come to take the next step."

Prior to the Bundesliga's suspension due to the coronavirus pandemic, Havertz scored six goals and set up another five, with Leverkusen fifth in the table.