The Pirates optioned Yorke to Triple-A Indianapolis on Sunday.
The 24-year-old started Saturday against Angels southpaw Yusei Kikuchi, going 0-for-1 with a walk before being replaced by a pinch hitter. Yorke collected four hits with a double, a stolen base and six RBI in his first two games after being called up in mid-August, but he's gone 3-for-20 across the ensuing 11 contests and has now lost his place on the MLB roster. Ronny Simon was recalled from Indianapolis in a corresponding move.