Falter was optioned to Triple-A Lehigh Valley on Thursday.
Falter was relatively effective as a spot starter against the Mariners on Wednesday, as he allowed a run on five hits and no walks while striking out four in 4.2 innings. However, the southpaw will head back to the minors after Zack Wheeler (illness) was reinstated from the COVID-19 injured list Thursday. Falter will be a candidate to rejoin the major-league club as a spot starter or relief option at some point.