The Nationals recalled Perez from Triple-A Rochester on Tuesday.
The arrival of Perez gives the Nationals a fresh arm out of the bullpen after Washington needed five relievers to cover all nine innings of Monday's 9-5 loss to Atlanta when starter Josiah Gray was scratched leading up to the contest. Perez has previously covered 5.1 innings in his six appearances out of the Washington bullpen this season, giving up three earned runs on six hits and six walks while striking out four.