diff --git a/src/raw/requests.rs b/src/raw/requests.rs
index 2f77422..681fca7 100644
--- a/src/raw/requests.rs
+++ b/src/raw/requests.rs
@@ -10,11 +10,10 @@ use crate::{
     transaction::HasLocks,
     BoundRange, ColumnFamily, Key, KvPair, Result, Value,
 };
-use tikv_client_store::{KvClient, RpcFnType, Store};
-
 use futures::{future::BoxFuture, prelude::*, stream::BoxStream};
 use kvproto::{kvrpcpb, tikvpb::TikvClient};
 use std::{mem, sync::Arc};
+use tikv_client_store::{KvClient, RpcFnType, Store};
 
 impl KvRequest for kvrpcpb::RawGetRequest {
     type Result = Option<Value>;
@@ -331,10 +330,7 @@ impl KvRequest for kvrpcpb::RawDeleteRangeRequest {
     fn reduce(
         results: BoxStream<'static, Result<Self::Result>>,
     ) -> BoxFuture<'static, Result<Self::Result>> {
-        results
-            .into_future()
-            .map(|(f, _)| f.expect("no results should be impossible"))
-            .boxed()
+        results.try_for_each(|_| future::ready(Ok(()))).boxed()
     }
 }
 
diff --git a/src/transaction/requests.rs b/src/transaction/requests.rs
index c826ccc..08d0663 100644
--- a/src/transaction/requests.rs
+++ b/src/transaction/requests.rs
@@ -346,10 +346,7 @@ impl KvRequest for kvrpcpb::PrewriteRequest {
     fn reduce(
         results: BoxStream<'static, Result<Self::Result>>,
     ) -> BoxFuture<'static, Result<Self::Result>> {
-        results
-            .into_future()
-            .map(|(f, _)| f.expect("no results should be impossible"))
-            .boxed()
+        results.try_for_each(|_| future::ready(Ok(()))).boxed()
     }
 }
 
@@ -408,10 +405,7 @@ impl KvRequest for kvrpcpb::CommitRequest {
     fn reduce(
         results: BoxStream<'static, Result<Self::Result>>,
     ) -> BoxFuture<'static, Result<Self::Result>> {
-        results
-            .into_future()
-            .map(|(f, _)| f.expect("no results should be impossible"))
-            .boxed()
+        results.try_for_each(|_| future::ready(Ok(()))).boxed()
     }
 }
 
@@ -456,10 +450,7 @@ impl KvRequest for kvrpcpb::BatchRollbackRequest {
     fn reduce(
         results: BoxStream<'static, Result<Self::Result>>,
     ) -> BoxFuture<'static, Result<Self::Result>> {
-        results
-            .into_future()
-            .map(|(f, _)| f.expect("no results should be impossible"))
-            .boxed()
+        results.try_for_each(|_| future::ready(Ok(()))).boxed()
     }
 }