It is not often that Liverpool flatter to deceive these days, but this was one of those rare matches in this season of enormous promise when the pretty numbers concealed something a little more grubby.
That is not a criticism or anything even approaching one - great virtue in the uglier wins, and all that logic - but for a long time, around 67 minutes to be precise, this truly was hard and scrappy work for Jurgen Klopp's side. So much so that Watford have the right to wonder.
What of the game-turning call by Jonathan Moss 10 minutes into the second half?