Joyce was placed on the 10-day injured list with a lower back strain Saturday.
Joyce returned from a calf injury in mid-May, but he saw sporadic playing time recently. He went 0-for-1 as a pinch hitter Friday, but he's now dealing with a back issue that will force him to spend more time on the injured list. Matt Vierling's contract was selected by the Phillies as part of a corresponding move.