"One month after his 33rd birthday, when he should be in his prime, youthful energy blending with maturity and know-how, Barry Zito finds himself in a tenuous and very challenging predicament.

He is trying to reinvent Barry Zito.

And this time he is serious.

As he wades through rehabilitation assignments in the minor leagues after a foot sprain, Zito seeks to ditch much of the identity he created through a decade of pitching in the majors in hopes of delivering to San Francisco a new and improved left-hander.

That is the heart of the message Zito offered Friday as he stood in front of his cubicle in the visitor's clubhouse at the O.co Coliseum, the site of his greatest success when he was a member of the A's.

"I've embraced (the concept) of taking a step back and working on some things while coming through the different levels," said Zito, who this month has made three minor league appearances, displaying solid command with moderate overall success.

He is painfully aware of his struggles as a San Francisco Giant. He is 40-58 through four-plus seasons (by contrast, he was 40-13 his first two full seasons in Oakland).

His time in San Jose and Fresno -- he will make one more rehab start -- serves not only to regain health but also to provide space to rededicate himself in hopes of exorcising the demons that formed when he became a Giant in 2007 and have stalked him ever since.

Something has to change, and he knows it. Hoping to save a career that at one time was quite impressive, a radical transformation might be his best chance to survive, much less thrive again, at the highest level.

"I become aware of too many things," Zito said. "And whether that's something I was born with or "... for some reason I just focus on the wrong things, I'll be the first to say it. My awareness is probably heightened.

"But that's no excuse. It's not an alibi. For me, it's about focus, about executing my pitch and letting everything else fall second to that. In the past, it seemed there were too many instances when the pitch fell second to other things."

Understand, now Zito is an inveterate self-analyst, constantly engaged in intrapersonal dialogue. That he is a searcher, a restless spirit, has been both liability and asset."