diff --git a/tsdb/index/index_test.go b/tsdb/index/index_test.go
index 2732a0d42b..930c2ba048 100644
--- a/tsdb/index/index_test.go
+++ b/tsdb/index/index_test.go
@@ -630,10 +630,8 @@ func BenchmarkReader_ShardedPostings(b *testing.B) {
 	require.NoError(b, iw.AddSymbol("unique"))
 
 	for i := 1; i <= numSeries; i++ {
-		require.NoError(b, iw.AddSeries(storage.SeriesRef(i), labels.Labels{
-			{Name: "const", Value: fmt.Sprintf("%10d", 1)},
-			{Name: "unique", Value: fmt.Sprintf("%10d", i)},
-		}))
+		require.NoError(b, iw.AddSeries(storage.SeriesRef(i),
+			labels.FromStrings("const", fmt.Sprintf("%10d", 1), "unique", fmt.Sprintf("%10d", i))))
 	}
 
 	require.NoError(b, iw.Close())