O'Rourke was designated for assignment by the Mets on Wednesday, Deesha Thosar of the New York Daily News reports.
O'Rourke has spent most of the season with Syracuse, compiling a 3.31 ERA, 1.49 WHIP and 33:17 K:BB in 32.2 innings. This move frees up a spot on New York's 40-man roster for Chris Mazza, who had his contract purchased from Triple-A Syracuse on Wednesday.