Royals manager Trey Hillman says Soria played catch on a flat surface at various distances. Hillman says Soria felt good.
Soria, who was second in the American League with 42 saves last season, is 1-0 with seven saves in as many opportunities and a 2.08 ERA in eight relief appearances this season.
Hillman said he did not know when Soria would throw off the mound.
Soria is eligible to come off the disabled list Saturday, but that appears unlikely. The Royals have lost five of seven games since Soria went on the DL.