The following is the third in a series of weekly stories on MLB.com examining each Major League club, position by position. Each Wednesday until Spring Training camps open, we'll preview a different position. Today: Middle infielders.

The middle of the infield could be the center of attention for the Giants during much of Spring Training.

Second base promises to be the site of spirited competition, with Ray Durham and Kevin Frandsen competing for the starting job and prospect Eugenio Velez providing additional intrigue.

Omar Vizquel remains virtually assured of the regular shortstop's role, but his level of performance is no longer a given, due to his age (40) and 49-point drop in batting average last year.

The Giants are expected to rely largely on airtight defense and a "small-ball" approach this season. Their keystone combination obviously will be essential to the former and integral to the latter.

"I think what we need is our guys to have the years that they're accustomed to having and their track record shows," Giants manager Bruce Bochy said, with the likes of Durham and Vizquel planted firmly in his mind. "If they have the years they're expected to have, we should put more runs on the board."

After ranking 15th among National League teams in runs in 2007, San Francisco's offense almost surely would improve with a resurgence from Durham, who slumped dramatically last season (.218, 11 home runs, 71 RBIs, compared with .293/26/93 in 2006). Giants general manager Brian Sabean called it a "lost year" for Durham, whose contract expires after this season -- a potential source of motivation. The Giants would be thrilled if Durham could hit somewhere around .274 with 15 homers, which are his averages in five seasons with San Francisco.

But Durham, 36, played sparingly in last season's final weeks and isn't assured of the starting job. Frandsen, 25, hit .370 in September and looked more comfortable with each passing day at second base. "He played as well as anybody on the club," Bochy said. "We'll do all we can to get him in there."

That could mean playing Frandsen at third base, if he and Durham prove worthy of starting and the Giants remain without a viable third-base alternative.

Velez, 25, is unlikely to leapfrog Durham and Frandsen, though he'll make his presence felt with his considerable speed. The switch-hitter showed off his acceleration during a 14-game September trial with the Giants and followed that by hitting .303 with 14 steals in 15 tries in 17 games with Scottsdale in the Arizona Fall League. Velez, who has played the outfield, still needs to settle in at one position and might begin the season at Triple-A Fresno to do just that.

San Francisco Giants
• Catchers: Molina's durability a plus
• Corner IF: Ortmeier has edge at first
• Middle IF: Second base up for grabs
• Outfielders: Youngsters to compete
• Starters: Youth is served
• Bullpen: Youngsters will be key
• Bench: Roster crunch in outfield
Entering his 20th Major League season and fourth with the Giants, Vizquel ought to have nothing to prove. But he'll be watched with skeptical eyes after hitting .246 in 2007, down from .295 the year before. Like Durham, Vizquel has more than just personal pride to goad him into improving. Vizquel must play in 140 games to activate a $5.2 million option for 2009, and he won't reach that goal unless he's healthy and productive enough to stay in the lineup.

At the very least, Vizquel's defense remains peerless. "It's still incredible," Sabean said.

Utilityman Rich Aurilia almost surely will spend time in the middle infield, as well as at the infield corners. Aurilia, who's healthy again after enduring neck and hamstring injuries last year, started seven games at second base and 11 at shortstop in '07.

Often criticized for not developing position players, the Giants appear primed to produce their next generation of middle infielders from within. Emmanuel Burriss and Brian Bocock, who'll be 23 when the season begins, are being groomed to inherit shortstop from Vizquel. Neither has played above high-Class A, however, so don't expect to see them at AT&T Park immediately. Burriss played five games at second base during a 17-game Arizona Fall League stint with Scottsdale, indicating that he could be a candidate for a position switch.

Nick Noonan, an 18-year-old second baseman/shortstop selected in the supplemental round (32nd overall) in last June's First-Year Player Draft, impressed the Giants immediately by hitting .316 in the Arizona Rookie League.