Roddick's serve continues to make him a target

In Memphis, Andy Roddick had a tough match. Again. In the first round, Mardy Fish was on the brink of set wins, and Australian Wayne Arthurs pushed him back to the same point.
This is never an encouraging comment to hear from an athlete (although true):

"I didn't think anyone could serve better than Mardy, but he did," Roddick said of Arthurs. "I never felt I had a chance on his serve. I was lucky to get through."

What happened to the "more aggressive" Andy? At some point, luck is just going to run out.