diff --git a/collector/metrics.go b/collector/metrics.go
index c293ecf3..c38a9f56 100644
--- a/collector/metrics.go
+++ b/collector/metrics.go
@@ -360,11 +360,13 @@ type PreloadStats struct {
 
 // Export exposes the preload stats.
 func (preloadStats *PreloadStats) Export(ch chan<- prometheus.Metric) {
-	metricsReplPreloadDocsNumTotal.Set(preloadStats.Docs.Num)
-	metricsReplPreloadDocsTotalMilliseconds.Set(preloadStats.Docs.TotalMillis)
+	if preloadStats != nil {
+		metricsReplPreloadDocsNumTotal.Set(preloadStats.Docs.Num)
+		metricsReplPreloadDocsTotalMilliseconds.Set(preloadStats.Docs.TotalMillis)
 
-	metricsReplPreloadIndexesNumTotal.Set(preloadStats.Indexes.Num)
-	metricsReplPreloadIndexesTotalMilliseconds.Set(preloadStats.Indexes.TotalMillis)
+		metricsReplPreloadIndexesNumTotal.Set(preloadStats.Indexes.Num)
+		metricsReplPreloadIndexesTotalMilliseconds.Set(preloadStats.Indexes.TotalMillis)
+	}
 }
 
 // StorageStats are the stats associated with the storage.