Bautista (elbow) threw a bullpen session Sunday in Baltimore, Nathan Ruiz of The Baltimore Sun reports.
It was his first mound workout since he was diagnosed three weeks ago with a partial tear of the UCL in his right elbow. Bautista appeared to be using his entire arsenal, per Ruiz, which is another encouraging development as the 28-year-old aims to return to the Orioles' active roster prior to the end of the regular season. Yennier Cano has been filling in as the O's primary closer.