Soria had been out since May 8 with a right rotator cuff strain. Pena went on the DL May 2 with a broken left hand.
Also, Sidney Ponson was placed on the 15-day disabled list due to a right elbow strain. The right-hander will rest the elbow for a few days before possibly beginning a throwing program.
The Royals put outfielder Coco Crisp on the bereavement list on Monday following the death of his great grandmother. He is expected to rejoin the team on Thursday.