diff --git a/pkg/ccl/backupccl/backup_job.go b/pkg/ccl/backupccl/backup_job.go
index 62cc97912d19..8c1e9f22fbb6 100644
--- a/pkg/ccl/backupccl/backup_job.go
+++ b/pkg/ccl/backupccl/backup_job.go
@@ -353,7 +353,7 @@ func backup(
 		return roachpb.RowCount{}, err
 	}
 
-	if backupinfo.WriteMetadataSST.Get(&settings.SV) {
+	if backupinfo.WriteMetadataSST.Get(&settings.SV) || backupinfo.TestWriteMetadataSST {
 		if err := backupinfo.WriteBackupMetadataSST(ctx, defaultStore, encryption, &kmsEnv, backupManifest,
 			tableStatistics); err != nil {
 			err = errors.Wrap(err, "writing forward-compat metadata sst")
diff --git a/pkg/ccl/backupccl/backupinfo/BUILD.bazel b/pkg/ccl/backupccl/backupinfo/BUILD.bazel
index a7ca79d41cfc..5d359950deec 100644
--- a/pkg/ccl/backupccl/backupinfo/BUILD.bazel
+++ b/pkg/ccl/backupccl/backupinfo/BUILD.bazel
@@ -33,6 +33,7 @@ go_library(
         "//pkg/sql/sem/tree",
         "//pkg/sql/stats",
         "//pkg/storage",
+        "//pkg/util",
         "//pkg/util/ctxgroup",
         "//pkg/util/encoding",
         "//pkg/util/hlc",
diff --git a/pkg/ccl/backupccl/backupinfo/manifest_handling.go b/pkg/ccl/backupccl/backupinfo/manifest_handling.go
index e45022ed3c60..e97ed5736d3d 100644
--- a/pkg/ccl/backupccl/backupinfo/manifest_handling.go
+++ b/pkg/ccl/backupccl/backupinfo/manifest_handling.go
@@ -39,6 +39,7 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/sql/pgwire/pgerror"
 	"github.com/cockroachdb/cockroach/pkg/sql/sem/tree"
 	"github.com/cockroachdb/cockroach/pkg/sql/stats"
+	"github.com/cockroachdb/cockroach/pkg/util"
 	"github.com/cockroachdb/cockroach/pkg/util/ctxgroup"
 	"github.com/cockroachdb/cockroach/pkg/util/encoding"
 	"github.com/cockroachdb/cockroach/pkg/util/hlc"
@@ -82,15 +83,18 @@ const (
 
 // WriteMetadataSST controls if we write the experimental new format BACKUP
 // metadata file.
-// kv.bulkio.rite_metadata_sst.enabled set to false by default due to
-// https://github.com/cockroachdb/cockroach/issues/85564.
 var WriteMetadataSST = settings.RegisterBoolSetting(
 	settings.TenantWritable,
 	"kv.bulkio.write_metadata_sst.enabled",
 	"write experimental new format BACKUP metadata file",
-	true,
+	false,
 )
 
+// TestWriteMetadataSST causes unit tests that run a backup to write the metadata sst with some
+// probability.
+var TestWriteMetadataSST = util.ConstantWithMetamorphicTestBool("write-metadata-sst",
+	WriteMetadataSST.Default())
+
 // IsGZipped detects whether the given bytes represent GZipped data. This check
 // is used rather than a standard implementation such as http.DetectContentType
 // since some zipped data may be mis-identified by that method. We've seen