As expected, third baseman Placido Polanco returned from the disabled list in time for Saturday's game against the Chicago Cubs at Wrigley Field.
His reinstatement cost utility infielder Juan Castro his job.
"Basically what happened ... is that other guys stepped up and were playing better baseball -- (Wilson) Valdez in particular," general manager Ruben Amaro said.
When the season started, Valdez was at triple-A Lehigh Valley and Castro, who signed a one-year $750,000 contract in the offseason, was considered the primary infield bench player. Valdez, however, got a chance to join the Phillies early in the season because of an injury to Jimmy Rollins and, despite briefly being outrighted back to Lehigh Valley in late May, consistently played better than Castro, who batted just .198 with 13 RBIs in 54 games.