I think Nixon had a bigger effect actually. Before he got injured, Manny had somewhat of a protection behind him. Now, teams are pitching to Ortiz, then just walking manny, and you either have Hinskie, or Pena, or Lopez!? batting behind Manny. Now that Manny's hurt, Ortiz gets nothing. I saw their lineup today, its just brutal.
edit: Cla Merideth and his 20 shutout innings could have helped too, KingPK.
edit2: 3 More Ks for A-Rod today. 1-15 in the series with 10 ks.