diff --git a/tools/flux/flux-helper.sh b/tools/flux/flux-helper.sh
index 25994df..f957b23 100755
--- a/tools/flux/flux-helper.sh
+++ b/tools/flux/flux-helper.sh
@@ -40,7 +40,7 @@ flux -h > /dev/null 2>&1 || die "flux is not in your path"
 
 FLUX_RANK_SET=$(flux jobs -no {ranks} ${FLUX_HELPER_JOBID})
 
-flux exec -r ${FLUX_RANK_SET} "${@}"
+flux exec -r "${FLUX_RANK_SET}" "${@}"
 
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