The Nationals placed Ribalta on the 15-day injured list Monday due to right forearm inflammation.
Ribalta hadn't appeared in a game since Tuesday before reporting forearm discomfort prior to Sunday's 7-5 loss to the Dodgers, per Mark Zuckerman of NatsJournal.com. According to Zuckerman, the Nationals are still awaiting the results of Ribalta's MRI, but the club had already concluded that his forearm injury was enough of a concern to force him to the shelf. He'll be eligible to come off the IL later this month, but it's possible that his 2026 campaign is over.