Betances was placed on the 10-day injured list Sunday with right lat tightness, Justin Toscano of The Bergen Record reports.
The 32-year-old took his first loss of the season Saturday after allowing one run on one hit while recording one out against the Yankees, and he'll now make his way to the injured list. Betances will be eligible to be activated Sept. 9, but it's unclear how long he's expected to be sidelined.