Infielder Matt Antonelli has retired from baseball. The report comes from MLBDailyDish.com's Chris Cotillo, who says Antonelli will become a student assistant next season at Wake Forest, where he went to college. A former first-round pick, Antonelli made it up to the majors for 21 games with the Padres in 2008 but had not come close to sniffing the big leagues since.