SCOTTSDALE, Ariz. -- Wednesday is a scheduled off-day for the Giants. Plenty of them would rather be working.

That's the only way the candidates for three vacant roles -- reliever, utility infielder and reserve outfielder -- can distinguish themselves enough to impress manager Bruce Bochy, general manager Brian Sabean and the rest of San Francisco's decision-making crew.

Then again, there's no rush. The Giants have 21 Cactus League games remaining, not counting the three-game Bay Bridge Series that ends the preseason, and Bochy has repeated that he'll deliberate as long as necessary before filling these jobs.

No clear favorite has emerged in any competition, though a few players have asserted themselves as legitimate contenders for a spot on the Opening Day roster.

Though the World Baseball Classic might inconvenience teams such as the Giants, whose ranks have been thinned by eight participants in the 16-team international tournament, it benefits the aspirants for one of the club's openings.

"You couldn't ask for more, if you're a young player, than to come into camp in this situation," Bochy said. "Most of the time when you come to camp, you're lucky to get a handful of at-bats. These guys are getting starts, they're getting at-bats every day and they're getting a chance to show what they can do, both on the position side and pitching side."

Here's a look at how each competition currently stands:

Reliever: Whoever wins this job likely will occupy the bullpen's least glamorous role, performing mostly in lopsided games or as a long reliever replacing an ineffective starter. Yet given the way Bochy uses his bullpen, this reliever will occasionally be asked to handle critical situations.

At least 10 individuals appear to have a chance at becoming the staff's 12th man: Chad Gaudin, Heath Hembree, Shane Loux, Jean Machi, Dan Otero, Yusmeiro Petit, Scott Proctor, Ramon Ramirez, Sandy Rosario and Dan Runzler.

Proctor has yielded one run in five innings spanning a team-high five appearances this spring. That last factoid indicates that San Francisco is giving him a careful look. As former starters, Gaudin, Loux and Petit could gain an advantage if the ability to pitch long relief becomes a prerequisite.

Hembree might have the best stuff among the bunch, but the Giants probably will assign him the closer's job at Triple-A Fresno or another significant role there until they decide that he's ready to stay in the big leagues, not just hang around the fringes.

Players whom the organization knows well or drafted often have an edge. This bodes well for the likes of Loux, Machi, Otero, Petit, Ramirez and Runzler.

Outfielder: The Giants need a right-handed batter to complement left-handed-batting Gregor Blanco, who remains the favorite to begin the season as the team's primary left fielder. Switch-hitting Andres Torres hit better right-handed (.286) than left-handed (.195) last year, but San Francisco could use another right-handed-batting presence to bring off the bench.

This potentially creates opportunities for Brett Pill, Cole Gillespie and Francisco Peguero.

Cited by club insiders when Spring Training began as a lock to start the season in Fresno, Peguero has forced his way into consideration by hitting .550 (11-for-20) in eight Cactus League games.

"That's the way you want it," Bochy said. "You want these guys to make it hard for you, like Peguero's doing."

Pill is accustomed to such competition, having won a spot on last year's Opening Day roster out of Spring Training. Primarily a first baseman, Pill must prove he can play left field competently enough to satisfy the defensive-minded Giants. Gillespie played 50 games with Arizona in 2011-12 and has nothing to prove at Triple-A.

Infielder: Having spent most of the past three seasons occupying this role for Philadelphia and Cincinnati, Wilson Valdez came to camp as a definite favorite to win this job. He has encountered several rivals.

Kensuke Tanaka, a non-roster invitee like Valdez, has received ample opportunity to prove himself. He leads all middle infielders in games (nine) and at-bats (24). But Tanaka, a three-time Gold Glove second baseman in Japan, must prove that he can handle shortstop to eclipse Valdez and earn an Opening Day roster berth. So far, that hasn't happened.

A long-shot candidate is Brock Bond, who's batting .500 (6-for-12) in seven games but has been saddled with a reputation for being a subpar defender. Bond might not open the season with San Francisco, but he appears to have aligned himself for an in-season promotion.

Tony Abreu was expected to push Valdez, but he has been hampered by a leg injury.

If the Giants don't like any of their alternatives, Ryan Theriot, who singled and scored the winning run in the 10th inning of last year's Game 4 World Series clincher, remains available as a free agent.