Schierholtz, 24, was batting .297 with 11 home runs, 48 RBIs and a .536 slugging percentage in his first 71 games for Triple-A Fresno. The Giants plan to leave the right fielder there until the opportunity for him to play every day in the Majors arises.
"There's not a spot right now to give him the playing time he needs," Giants manager Bruce Bochy said Thursday. "Sometime there will be. He's doing what he needs to do. He's playing great ball down there. He can't control some things."
Bochy emphasized that he wasn't implying a trade was imminent that could vault Schierholtz into a regular role with San Francisco. His chance, said Bochy, "may not be this year."
Villalona, 17, was hitting .237 with nine homers and 32 RBIs for Class A Augusta. The corner infielder also had 15 doubles and 29 runs. Villalona, a native of the Dominican Republic, has ranked among the Giants' most heralded prospects since he received a $2.1 million signing bonus at age 16 in 2006.
"My friends that played in the game last year told me about the experience and how much fun it is and I can't wait," Villalona said in a statement released by the Augusta club.
Pucetas, 23, is 7-0 with a 2.76 ERA in 12 starts for Class A San Jose. He also has 51 strikeouts and 15 walks in 65 1/3 innings. Named Class A Starting Pitcher of the Year by MiLB.com last season after finishing 15-4 with a 1.86 ERA, the right-hander owns a 29-5 career record in three Minor League seasons.
Futures Game veterans among current Giants include left-hander Barry Zito (2000), infielder Jose Castillo (2003), right-hander Merkin Valdez (2003-04), right-hander Matt Cain (2004) and infielder Kevin Frandsen (2005).
Chris Haft is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.