SAN FRANCISCO -- Edgar Renteria was activated and Mike Fontenot started on Wednesday, but Juan Uribe will get the majority of starts at shortstop for the rest of the season, Giants manager Bruce Bochy said.

Despite Renteria being active for the first time since mid-August, Bochy decided to give Fontenot his third start at shortstop as a Giant, and first since Aug. 21.

Renteria was hitting .278 with two home runs and 21 RBIs before missing 19 games due to a left biceps strain suffered in mid-August. Bochy said Renteria will more than likely start at short when Uribe does not.

Uribe, who has hit .249 with 17 home runs and 71 RBIs, has appeared in 81 games at shortstop and could use a breather, Bochy said.

"We pushed him pretty hard," Bochy said. "He's been out there, for the most part, every day, and it looks like he's getting more starts than ever, so he needs a day."

Giants add four to roster, undecided on more

SAN FRANCISCO -- The Giants added four players to their active roster on Wednesday, the first day Major League teams could expand rosters, but they're still undecided if they will add more in the coming days.

Shortstop Edgar Renteria and left-handed reliever Dan Runzler were reinstated from the 15-day disabled list, while outfielder Darren Ford was recalled from Double-A Richmond.

The Giants also will activate right-handers Chris Ray and Guillermo Mota when they are eligible to come off the disabled list on Friday and Sept. 8, respectively.

Ford, a 24-year-old outfielder, will be making his Major League debut when he sees his first action. In 113 games at Richmond, he hit .251 with 20 doubles, nine triples and five home runs. He also stole 37 bases in 52 attempts, making him a likely pinch-runner late in games.

"I'd say that's a big reason he's here," Giants manager Bruce Bochy said. "Also possibly to play some defense, get a bunt down, things like that."

Bochy said he and general manager Brian Sabean will continue to discuss whether the Giants will call up other players after Triple-A Fresno's season ends. Entering Wednesday, the Grizzlies were 2 1/2 games out of first place with six to play.

"A lot depends on how things go here, which will determine if we need to bring somebody up before their season is over," Bochy said. "Knock on wood, it's not an injury or a long extra-inning game, something like that."

Three prospects to play in Arizona Fall League

SAN FRANCISCO -- Three Giants infield prospects, including power-hitting first baseman Brandon Belt, will take part in the Arizona Fall League after the regular season.

Belt, second baseman Charlie Culberson and third baseman Conor Gillaspie will play for the Scottsdale Scorpions, whose season begins on Oct. 12.

Entering Wednesday, Belt was hitting .358 with 22 homers and 110 RBIs in 130 games between Class A San Jose, Double-A Richmond and Triple-A Fresno. The club's 2009 fifth-round Draft pick also has posted a .461 on-base percentage and slugged .627.

Culberson -- one of the Giants' 2007 first-round picks -- was hitting .297 with 15 home runs, 70 RBIs and 23 stolen bases, while Gillaspie -- one of the Giants' '08 first-round picks -- is hitting .290 with six home runs and 63 RBIs, both for San Jose.