I didn't see the game, and haven't really seen him that much in Liverpool.
I watched him weekly in Valencia though and I never understood the fuss about him. I especially remember one game, where the right back get injured and Sissoko takes his place. I've never seen a player being made more of a fool, they dribbled past him with ease every single time. I know it isn't his position but it really gave me an idea of his marking skills.