Psychological advantages can be huge in terms of achievement. Arsenal went 46(?) games unbeaten until we defeated them and then suddenly Arsenal looked far from invincible.
Do not underestimate the knock-on effect this home loss will have on them. It won't stop them mounting the serious challenge that we know they will pose, but in terms of looking unbeatable, either at Anfield or away, they won't be so impossible to get points from anymore. The quality is still there, but the psychological edge is gone.