Manager Don Mattingly, who watched the session, was evasive about the next step for Ryu, assuming he comes out of this workout without a setback.
"There's talk of having him do something to pitch here," said Mattingly. "Exactly what that will be, we have a good idea, but we'd rather wait till tomorrow."
Translated, that seems to mean a simulated game is most likely the next step, perhaps as soon as Friday in Arizona. At the soonest, Ryu could slide back into Paul Maholm's spot in the rotation next Wednesday in New York, unless the decision is made to send him out for a Minor League rehab start.
Prior to Ryu's bullpen session, Chad Billingsley threw 20 pitches off the mound as he rebounds after a setback during his rehab from Tommy John surgery.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.