Why was O'Hara marking Laursen ? Ah well ...
O'Hara should not have been marking Laursen but....
Losing Kaboul lost us one tall defender. Huddlestone for Boateng should have made no height difference except that the Hud has proved recently that he's as bad as Daws at marking at set pieces.
I would like to see who was marking whom? Daws still had Melberg (in his own inimitable fashion). Zokora had Agbonlahor. Who was Jenas marking? Who was Huddlestone marking? Was Berba on near post duties?
Whatever... The bottom line is that somebody taller than O'Hara had to be given the job of marking Laursen. And that's down both to Ramos and the players on the pitch.