diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index 47cc6cc55..0760dc291 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -2008,6 +2008,18 @@ ngx_http_upstream_send_request(ngx_http_request_t *r, ngx_http_upstream_t *u,
             return;
         }
 
+        if (c->write->ready && c->tcp_nopush == NGX_TCP_NOPUSH_SET) {
+            if (ngx_tcp_push(c->fd) == -1) {
+                ngx_log_error(NGX_LOG_CRIT, c->log, ngx_socket_errno,
+                              ngx_tcp_push_n " failed");
+                ngx_http_upstream_finalize_request(r, u,
+                                               NGX_HTTP_INTERNAL_SERVER_ERROR);
+                return;
+            }
+
+            c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
+        }
+
         return;
     }