diff --git a/integration_test.go b/integration_test.go
index f1530a01..38f375c6 100644
--- a/integration_test.go
+++ b/integration_test.go
@@ -1770,7 +1770,7 @@ func BenchmarkMarshal_ReuseMsg(b *testing.B) {
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		a := data[r.Intn(len(data))]
-		seg, err := msg.Reset(msg.Arena)
+		seg, err := msg.Reset(capnp.SingleSegment(nil))
 		if err != nil {
 			b.Fatal(err)
 		}
diff --git a/message_test.go b/message_test.go
index 5bd8448c..4d3289b3 100644
--- a/message_test.go
+++ b/message_test.go
@@ -646,11 +646,11 @@ var errReadOnlyArena = errors.New("Allocate called on read-only arena")
 
 func BenchmarkMessageGetFirstSegment(b *testing.B) {
 	var msg Message
-	var arena Arena = SingleSegment(nil)
 
 	b.ResetTimer()
 	b.ReportAllocs()
 	for i := 0; i < b.N; i++ {
+		arena := SingleSegment(nil)
 		_, err := msg.Reset(arena)
 		if err != nil {
 			b.Fatal(err)