Selection, location or mechanics...?

...you tell me. After last night's pounding against the timely hitting D'back offense there are several explanations as to what went wrong with Derek Lowe's stuff:

"Those type of starts obviously are not going to get it done,"
said Lowe. "This is not a trial-and-error session. My job is to
pitch deep into games and I haven't done it in a month."

Lowe scoffed at the suggestion that the three effective innings
were a positive to build on.

"Yeah, if you're a rookie," said the nine-year veteran.
"There comes a point in time where I have to make better pitches.
Now it seems like when I make them, they get hit.
And when I make mistakes, it's punishing, an extra-base hit or
a home run. It's not for lack of effort or concentration.
It comes down to execution. I'm beyond frustration.
The results are horrible."

Lowe repeated the theory that pitch selection is part
of his problem. He said he abandoned the curveball against Arizona
and succeeded with the sinker early, but felt he had to change
the pitch selection the next time through the lineup,
which is exactly when the Diamondbacks awoke.
He's clearly not trusting his stuff.

"Right now, I'm fighting when to throw the breaking ball," he said.

Little praised Lowe's stuff, but said he mislocated pitches.
Arizona outfielder Luis Gonzalez, however, said Lowe's sinker
flattened out after the second inning.