The Nationals optioned Ribalta to Triple-A Rochester on Sunday.
Four days after being recalled from Triple-A, Ribalta will now head back to the minors after giving up two earned runs on four hits and a walk over one-third of an inning during Sunday's loss to the Cubs. While the 26-year-old has yet to find his footing in the big leagues, he's been effective at Rochester with a 3.64 ERA and 1.27 WHIP across 29.2 frames.