The Belgian is injured and will be replaced by Adam Bogdan.
The Belgian again looked like a weak and timid presence from deliveries into the box and Liverpool fans continue to remain frustrated with the inconsistent stopper.
With that in mind Jurgen Klopp has come out this week in defence of Mignolet - who he insists is the number one keeper at Liverpool for now and the future.
However his performance last week did see him rumoured for the chop.
Well it now looks like Simon Mignolet will indeed be missing for tomorrow's game against Watford - but he has not been dropped.
It has been reported by Het Nieuwsblad in Belgium that Mignolet will miss the game v Watford tomorrow after picking up a hamstring problem against The Baggies which he has not yet recovered from.
With Mignolet seemingly out of action it will had a chance to Hungarian goalie Adam Bogdan to shine in the sticks for Liverpool tomorrow afternoon - with his eyes on the prize full-time.