McManaman says the German is probably on Jurgen Klopp's radar - although, we won't know about it.
"It's one of those transfers where there's a young player with plenty to improve on, who might be the type of player that Liverpool are looking at rather than a fully-fledged superstar.
"He is one who's impressed in the Bundesliga this season and Jurgen Klopp certainly knows the Bundesliga and he has a lot of friends in that league, so he's got a lot of people to call to get opinions on players.
"Normally Liverpool do a lot of their transfer business very secretly don't they? When they've brought in players previously, we've hardly known about them and they've not been confirmed transfer targets for while, with Virgil van Dijk being the exception.
"A lot of the other players were bought when we didn't know it was happening, such as the likes of Alisson Becker and Fabinho."