diff --git a/object-file.c b/object-file.c
index d7e153c1b9..1b62996ef0 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1994,15 +1994,8 @@ static void odb_transaction_files_commit(struct odb_transaction *base)
 {
 	struct odb_transaction_files *transaction = (struct odb_transaction_files *)base;
 
-	/*
-	 * Ensure the transaction ending matches the pending transaction.
-	 */
-	ASSERT(base == base->source->odb->transaction);
-
 	flush_loose_object_transaction(transaction);
 	flush_packfile_transaction(transaction);
-	base->source->odb->transaction = NULL;
-	free(transaction);
 }
 
 struct odb_transaction *odb_transaction_files_begin(struct odb_source *source)
@@ -2017,8 +2010,6 @@ struct odb_transaction *odb_transaction_files_begin(struct odb_source *source)
 	transaction->base.source = source;
 	transaction->base.commit = odb_transaction_files_commit;
 
-	odb->transaction = &transaction->base;
-
 	return &transaction->base;
 }
 
diff --git a/odb.c b/odb.c
index 349b4218a5..1679cc0465 100644
--- a/odb.c
+++ b/odb.c
@@ -1153,7 +1153,12 @@ void odb_reprepare(struct object_database *o)
 
 struct odb_transaction *odb_transaction_begin(struct object_database *odb)
 {
-	return odb_transaction_files_begin(odb->sources);
+	if (odb->transaction)
+		return NULL;
+
+	odb->transaction = odb_transaction_files_begin(odb->sources);
+
+	return odb->transaction;
 }
 
 void odb_transaction_commit(struct odb_transaction *transaction)
@@ -1161,5 +1166,12 @@ void odb_transaction_commit(struct odb_transaction *transaction)
 	if (!transaction)
 		return;
 
+	/*
+	 * Ensure the transaction ending matches the pending transaction.
+	 */
+	ASSERT(transaction == transaction->source->odb->transaction);
+
 	transaction->commit(transaction);
+	transaction->source->odb->transaction = NULL;
+	free(transaction);
 }