Guerra was the team closer when last season started, but he lost that job, suffered three injuries and required surgeries to his right knee and shoulder.
He did not make the Major League team out of Spring Training and was sent to Albuquerque for a starting role, not to turn him into a starter but to extend him into a multiple-inning long reliever. In four starts for the Isotopes, he was 0-2 with a 4.02 ERA and last pitched Friday.
Wall, who was recalled from Albuquerque April 15 after Shawn Tolleson was injured, made six appearances and had an ERA of 18.00.
Guerra is the 17th pitcher the Dodgers have had in uniform this month.
Ken Gurnick is a reporter for MLB.com. Austin Laymance is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.