diff --git a/datafusion/core/src/physical_plan/sorts/merge.rs b/datafusion/core/src/physical_plan/sorts/merge.rs
index e191c044b9040..736df7dbe81a1 100644
--- a/datafusion/core/src/physical_plan/sorts/merge.rs
+++ b/datafusion/core/src/physical_plan/sorts/merge.rs
@@ -15,6 +15,9 @@
 // specific language governing permissions and limitations
 // under the License.
 
+//! Merge that deals with an arbitrary size of streaming inputs.
+//! This is an order-preserving merge.
+
 use crate::physical_plan::metrics::BaselineMetrics;
 use crate::physical_plan::sorts::builder::BatchBuilder;
 use crate::physical_plan::sorts::cursor::Cursor;
@@ -51,8 +54,9 @@ macro_rules! merge_helper {
     }};
 }
 
-/// Perform a streaming merge of [`SendableRecordBatchStream`]
-pub(crate) fn streaming_merge(
+/// Perform a streaming merge of [`SendableRecordBatchStream`] based on provided sort expressions
+/// while preserving order.
+pub fn streaming_merge(
     streams: Vec<SendableRecordBatchStream>,
     schema: SchemaRef,
     expressions: &[PhysicalSortExpr],
diff --git a/datafusion/core/src/physical_plan/sorts/mod.rs b/datafusion/core/src/physical_plan/sorts/mod.rs
index 567de96c1cfdf..dff39db423f0a 100644
--- a/datafusion/core/src/physical_plan/sorts/mod.rs
+++ b/datafusion/core/src/physical_plan/sorts/mod.rs
@@ -20,7 +20,7 @@
 mod builder;
 mod cursor;
 mod index;
-mod merge;
+pub mod merge;
 pub mod sort;
 pub mod sort_preserving_merge;
 mod stream;