He made one really bad decision. Other than that, a normal give and take in the game. But that decision was absurdly harsh and game changing and early, so I think that has to play into it.
Clattenberg on the other hand, lots of bad one sided no calls. He chose incorrectly to just let them play. That cost us 1 or 2 pks, kuyt a redcard, and plenty of others that just aren't coming to mind.
I'm usually a fan of refs just letting them play, but I still think that clattenbergs lack of calls was far worse that atkinsons interference.
Edit- forgot about gerrard talking clat into the red on hibbo. That one alone nearly equalled today's injustice, so everything else he screwed up that day is what sets that game apart.