SAN FRANCISCO -- On the day Matt Hague was optioned to Indianapolis, Clint Hurdle's starting lineup offered evidence why he went, and not someone like Josh Harrison.

While general manager Neal Huntington talked about Hague's assignment in Triple-A allowing him to alternate series at third and first base because "switching every day does not make a whole lot of sense," Harrison made his third consecutive start at a third different position.

Harrison was at third base against Giants lefty Barry Zito. He had started at second Thursday, then at short in Friday's series opener here.

"Completing my tour of the infield," Harrison said with a smile.

Harrison, as well as Yamaico Navarro, offer more defensive flexibility than Hague, primarily a first baseman during four seasons in the Minors who is still trying to get adjusted to third.

"Right now, Matt would be our fifth-best defender at third," Hurdle said, "and that means you aren't going to get a lot of reps."

The depth chart thus had Hague behind Pedro Alvarez, Casey McGehee, Harrison and Navarro. McGehee also mixing it up at first with Garrett Jones seriously narrowed Hague's possibilities, and the Pirates did not want to limit him to pinch-hitting duties.

Pirates waiting for Alvarez to 'flip the switch'

SAN FRANCISCO -- Right now, Pedro Alvarez is simply a Not Ready For Prime-Time Player. That doesn't make him an alumnus of the original "Saturday Night Live" troupe, just a very frustrated Major League hitter.

And it makes Clint Hurdle a very confused manager. Daily, Hurdle sees Alvarez work and hit hard before games. During them, Alvarez has been a study in frustration.

"His early work can't be any better. There's no room for improvement in his cage work, in his early work, in his batting practice -- none! It can't be done any better," Hurdle said, emphatically and convincingly. "The transition is going to come when he's able to flip the switch in a game."

Alvarez's inability to switch up his game performance has kept him the most polarizing athlete in Pittsburgh. He was on the bench Saturday night with a lefty (Barry Zito) on the mound for the Giants, dooming him for one more day with a line of 10 strikeouts and one hit in 16 at-bats.

"It's like going from the driving range to the tee, with people watching," Hurdle said. "He's got to find a way to clean the slate mentally. Don't wrestle with the game. Just go play it.

"You're seeing what we're seeing once the game starts. I could send videotape of his early work to the 10 best hitting coaches who ever lived -- foot down, hands in the power position, belly button toward the direction the ball goes. It's a blueprint, and he knows it. The hard part is making that transition into the game."

Worth noting

• Gerrit Cole came back to earth in his second start for Class A Bradenton on Saturday, lasting only three innings against Fort Myers and being charged with four runs (three earned) and four hits. Cole had allowed one run in his four-inning debut, against Palm Beach on Monday.

• Saturday night's loss was the Pirates' fifth straight. In 2011, they did not have a losing streak of more than four games until May 10-16.

• The regular right side of the Pirates' infield -- third baseman Pedro Alvarez and shortstop Clint Barmes -- has combined for three hits, three errors and 18 strikeouts.

• Casey McGehee, playing the still-unfamiliar position of first base, made several impressive plays Saturday on hard smashes. McGehee had four unassisted plays.

The Last Word: "Triple-A is the worst level of baseball. Nobody wants to be there." -- Pirates GM Neal Huntington, talking about the almost-but-not-quite-there rung of baseball's ladder.