diff --git a/broker.go b/broker.go
index d27ebd22d..9ca41c91e 100644
--- a/broker.go
+++ b/broker.go
@@ -1367,6 +1367,7 @@ func (b *Broker) unregisterMetrics() {
 	for _, name := range b.registeredMetrics {
 		b.conf.MetricRegistry.Unregister(name)
 	}
+	b.registeredMetrics = nil
 }
 
 func (b *Broker) registerMeter(name string) metrics.Meter {