diff --git a/go/vt/discovery/topology_watcher_test.go b/go/vt/discovery/topology_watcher_test.go
index afa44f185b4..1fcc0d3306b 100644
--- a/go/vt/discovery/topology_watcher_test.go
+++ b/go/vt/discovery/topology_watcher_test.go
@@ -595,6 +595,11 @@ func TestNewFilterByTabletTags(t *testing.T) {
 	assert.False(t, filter.IsIncluded(&topodatapb.Tablet{
 		Tags: map[string]string{},
 	}))
+	assert.True(t, filter.IsIncluded(&topodatapb.Tablet{
+		Tags: map[string]string{
+			"instance_type": "i3.xlarge",
+		},
+	}))
 	assert.True(t, filter.IsIncluded(&topodatapb.Tablet{
 		Tags: tags,
 	}))