Perez (elbow) threw a bullpen session Saturday, Daniel Alvarez-Montes of ElExtraBase.com reports.

Saturday marks the first time Perez has thrown off a mound since experiencing inflammation in his right elbow. He threw 20 pitches during his first session and used his entire arsenal of pitches, with everything seeming to go smoothly. He'll likely require a few more mound sessions before moving to facing live hitters, and a minor-league rehab assignment should come after that.