diff --git a/tsdb/shard.go b/tsdb/shard.go
index 6bbdfb4e7b..dec2dc50ce 100644
--- a/tsdb/shard.go
+++ b/tsdb/shard.go
@@ -18,6 +18,7 @@ import (
 	"github.com/gogo/protobuf/proto"
 	"github.com/influxdata/influxdb/influxql"
 	"github.com/influxdata/influxdb/models"
+	"github.com/influxdata/influxdb/pkg/estimator"
 	internal "github.com/influxdata/influxdb/tsdb/internal"
 	"go.uber.org/zap"
 )
@@ -487,6 +488,20 @@ func (s *Shard) SeriesN() int64 {
 	return s.engine.SeriesN()
 }
 
+// SeriesSketches returns the series sketches for the shard.
+func (s *Shard) SeriesSketches() (estimator.Sketch, estimator.Sketch, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.engine.SeriesSketches()
+}
+
+// MeasurementsSketches returns the measurement sketches for the shard.
+func (s *Shard) MeasurementsSketches() (estimator.Sketch, estimator.Sketch, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.engine.MeasurementsSketches()
+}
+
 func (s *Shard) createFieldsAndMeasurements(fieldsToCreate []*FieldCreate) error {
 	if len(fieldsToCreate) == 0 {
 		return nil
diff --git a/tsdb/store.go b/tsdb/store.go
index 703676674f..6211432aca 100644
--- a/tsdb/store.go
+++ b/tsdb/store.go
@@ -714,7 +714,7 @@ func (s *Store) SeriesCardinality(database string) (int64, error) {
 		if sh == nil {
 			return nil, nil, errors.New("shard nil, can't get cardinality")
 		}
-		return sh.engine.SeriesSketches()
+		return sh.SeriesSketches()
 	})
 }
 
@@ -725,7 +725,7 @@ func (s *Store) MeasurementsCardinality(database string) (int64, error) {
 		if sh == nil {
 			return nil, nil, errors.New("shard nil, can't get cardinality")
 		}
-		return sh.engine.MeasurementsSketches()
+		return sh.MeasurementsSketches()
 	})
 }