It is perhaps the biggest mystery of the Premier League season: what on Earth has happened to Liverpool?
Manager Jurgen Klopp's so-called "mentality monsters" have become fragile and erratic, a team who can follow a 7-0 win over Manchester United with 0-1 defeat at Bournemouth, and a team who can lose 2-5 at home to Real Madrid yet fight back superbly to draw with Arsenal, as they did last week.
Klopp has looked dumbfounded with what he is watching as his "heavy metal" football has seemed like an out of tune quartet at times.