Ailing second baseman Cesar Hernandez has been placed on the 10-day disabled list with an oblique strain suffered while making a throw during Friday night's loss at Busch Stadium.
To fill Hernandez's roster spot, the Phils have activated reliever Joaquin Benoit, who was on the disabled list with a knee injury.
Losing Hernandez's bat will be an issue for an already sputtering Phillies offense that averages just 3.95 runs per game (fourth worst in the majors) and was shut out, 7-0, by the Cardinals on Saturday without its leadoff man in the lineup.
A fixture at the top of the Phillies lineup all season long, Hernandez is batting .277 with with five home runs, 10 doubles, two triples and 14 RBI.
In Hernandez's absence, Howie Kendrick is expected to take over at second base. Kendrick also suffered an oblique injury this season and missed six weeks of playing time.
In 23 appearances this season as a member of the back end of the Phils' bullpen, Benoit, a free-agent signing this past offseason, has a 1-2 record with 3.68 ERA and a save.