HOUSTON -- Center fielder Gary Brown heads the list of Giants farmhands selected to hone their skills with the Scottsdale Scorpions in the Arizona Fall League, which begins play Oct. 9.

Brown, rated San Francisco's No. 1 prospect in MLB.com's Prospect Watch, will participate in the AFL for the second straight year. He'll turn 24 on Sept. 28. The organization's top selection in the 2010 First-Year Player Draft, Brown entered Wednesday batting .281 with seven home runs, 42 RBIs and 33 stolen bases in 51 tries for Double-A Richmond.

Shortstop Joe Panik and first baseman Ricky Oropesa, who have spent this season with the Giants' Class A San Jose affiliate, also will play for the Scorpions. Pitchers are yet to be determined.

Rated the Giants' No. 5 prospect by MLB.com, Panik took a .294 batting average, a .368 on-base percentage, seven home runs and 75 RBIs into Wednesday. Panik, who will turn 22 on Oct. 30, was the Giants' top Draft pick last year.

Oropesa, 23, entered Wednesday hitting .258 with 15 homers, 94 RBIs and a .418 slugging percentage. The left-handed-batting Oropesa, San Francisco's third-round pick in the 2011 Draft, is rated 14th among Giants prospects by MLB.com.

Giants manager Bruce Bochy endorsed the AFL as a training ground for promising young players. He observed that winter leagues, by contrast, emphasize winning.

"If you have a certain thing that you want your player to work on, the Fall League makes it a lot easier," Bochy said.

Affeldt returns as Hensley hits disabled list

HOUSTON -- The Giants restored left-hander Jeremy Affeldt to their bullpen Wednesday and cleared roster room for him by placing right-hander Clay Hensley on the 15-day disabled list with a strained right groin.

Affeldt used exactly one day of his three-day paternity leave and rejoined the team after his wife, Larissa, gave birth to their third son, Kolt Kristopher, on Tuesday. The need to create a vacancy for Affeldt prompted the Giants to shelve Hensley, who hurt himself while pitching. Hensley has allowed nine runs and 10 hits spanning 5 2/3 innings in his last eight games, hiking his ERA from 2.95 to 4.37.

"He hasn't been as sharp with his command," Bochy said, citing a difference in Hensley's performance since he sustained his injury.

Biggio reflects on move away from catching

HOUSTON -- An offensively talented catcher establishes himself in the Major Leagues. His diverse skills make him an extremely valuable performer. But common sense dictates that he ultimately should move to another position to maximize his hitting prowess.

That summarizes Buster Posey's situation with the Giants as they debate, mostly in private, when and whether to make him a first baseman. If anybody knows the impact a position switch can make, it's Craig Biggio, the ex-Astro who's on the upcoming Hall of Fame ballot.

Biggio finished his 20-year career, which he spent entirely in Houston, with 3,060 hits. He became a second baseman in 1992 after primarily catching through his first four big league seasons. Though he won a Silver Slugger trophy and made an All-Star team behind the plate, he truly flourished at second base. He made six All-Star teams, won four Gold Glove awards, twice led the National League in runs scored, earned four more Silver Slugger awards and finished among the top 10 in Most Valuable Player voting three times once he shed his catcher's gear.

Unlike Posey, Biggio can look back on his playing days and comprehend the effects of his conversion.

"It was the best thing that ever happened to me and the best thing that ever happened to the Houston Astros," Biggio said. "But in the beginning, it was a tough decision to make, because I loved [catching] so much."

Biggio acknowledged that catching's rigors can be hazardous to a hitter.

"It's vivid in my mind," he said. "In my last at-bat [of a game as a catcher], I didn't give it up. But you're tired, you're beat up, you're exhausted. I remember going into my last at-bat playing infield, I felt great. I felt like I did in my first at-bat. So the physical wear and tear and the grinding take its toll on you. Especially at this time of the year."

Biggio endorsed the Giants' occasional use of Posey at first base.

"I like the idea of trying to give him a little bit of a break and put him there," Biggio said. "That's really, really smart."

Biggio refrained from offering an opinion regarding what the Giants should do with Posey. But he did offer encouragement.

"It'll be a tough decision for them to make. But if anybody knows, Boch does," Biggio said, referring to manager Bruce Bochy. "I have the utmost respect for him. He's an unbelievable manager."