Melvin's use of Leone

Further adding doubt to releasing Aurilia and having a rookie play, here is Melvin's response per the seattle times and Leone:

Last night, Aurilia was at shortstop, and Justin Leone started at third base. Melvin said he would not "run Leone out there every day."

Further proof Melvin is an idiot. Let's see, the kids been playing baseball now his entire adult life, and Melvin figures pinch hits and occasional starts are the best way to see what this kid can do.

Can anyone explain why Melvin refuses to play Leone more often?