diff --git a/jsonnet/kube-prometheus/addons/managed-cluster.libsonnet b/jsonnet/kube-prometheus/addons/managed-cluster.libsonnet
index 5b37c56e..f9032abd 100644
--- a/jsonnet/kube-prometheus/addons/managed-cluster.libsonnet
+++ b/jsonnet/kube-prometheus/addons/managed-cluster.libsonnet
@@ -27,7 +27,7 @@
 
   // Same as above but for ServiceMonitor's
   local p = super.prometheus,
-  prometheus: {
+  prometheus+: {
     [q]: p[q]
     for q in std.objectFields(p)
     if !std.setMember(q, ['serviceMonitorKubeControllerManager', 'serviceMonitorKubeScheduler'])