Shewmake is out of the lineup for Wednesday's game against the Nationals.
Shewmake will join fellow left-handed hitters LaMonte Wade and Taylor Trammell on the bench while the Astros stock up on some extra right-handed bats to counter Nationals southpaw Foster Griffin. Nick Allen will replace Shewmake at shortstop Wednesday, though both players are likely to see their opportunities in the middle infield dwindle this weekend, when Jeremy Pena (calf) is expected to return from the injured list.