The Nationals optioned Poulin to Triple-A Rochester on Wednesday, Mark Zuckerman of NatsJournal.com reports.
Poulin has been deployed in a variety of roles for the Nationals this season and is one of seven relievers on the roster to notch a save. However, while he's managed a 2.91 ERA, a 16:14 K:BB over 21.2 innings is less appetizing. Clayton Beeter (forearm) is expected to come off the injured list Thursday in a corresponding move.