diff --git a/Configuration/PyReleaseValidation/python/MatrixReader.py b/Configuration/PyReleaseValidation/python/MatrixReader.py
index 8113eb3d71352..54b78ca9a3398 100644
--- a/Configuration/PyReleaseValidation/python/MatrixReader.py
+++ b/Configuration/PyReleaseValidation/python/MatrixReader.py
@@ -22,7 +22,7 @@ def __init__(self, opt):
 
         self.wm=opt.wmcontrol
         self.revertDqmio=opt.revertDqmio
-        self.addCommand=' '.join(opt.command)
+        self.addCommand=opt.command
         self.apply=opt.apply
         self.commandLineWf=opt.workflow
         self.overWrite=opt.overWrite
diff --git a/Configuration/PyReleaseValidation/scripts/runTheMatrix.py b/Configuration/PyReleaseValidation/scripts/runTheMatrix.py
index 797004f26d310..263b5f8106724 100755
--- a/Configuration/PyReleaseValidation/scripts/runTheMatrix.py
+++ b/Configuration/PyReleaseValidation/scripts/runTheMatrix.py
@@ -306,6 +306,7 @@ def runSelected(opt):
                       action='store')
 
     opt,args = parser.parse_args()
+    if opt.command: opt.command = ' '.join(opt.command)
     os.environ["CMSSW_DAS_QUERY_SITES"]=opt.dasSites
     if opt.IBEos:
       try:from commands import getstatusoutput as run_cmd