Hernandez will have the surgery performed by Andrews on Tuesday and will be lost for the entire 2014 season.
"It's disappointing, but we have to regroup," D-backs manager Kirk Gibson said when Hernandez was first diagnosed. "I don't have an answer for who will be there, but we do have some guys with experience in the back end. Our bullpen will have a different dynamic, but it's just another opportunity for someone else. We still have a lot of good choices."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.