Bayer Leverkusen manager Peter Bosz accepts they're on borrowed time regarding young midfielder Kai Havertz.

Last season was the finest of Havertz's career thus far, scoring 17 goals in 34 appearances from midfield, as well as notching four assists for his teammates.

As a result, multiple reports claim both Manchester clubs as well as Liverpool , Bayern Munich and Real Madrid are keeping tabs on his situation at Leverkusen.

"Of course I would like to keep him, just as I would have liked to keep Julian Brandt, for example," Bosz told the BILD.

"Kai is only 20 and still has room for improvement. I can help him there.

"But it is like this, at the end the player himself must feel when he is ready for the next step.

"Nobody can decide that for him."