diff --git a/Lib/test/test_asyncio/test_subprocess.py b/Lib/test/test_asyncio/test_subprocess.py
index 428510f..235813a 100644
--- a/Lib/test/test_asyncio/test_subprocess.py
+++ b/Lib/test/test_asyncio/test_subprocess.py
@@ -228,6 +228,7 @@
         proc, large_data = self.prepare_broken_pipe_test()
 
         async def write_stdin(proc, data):
+            await asyncio.sleep(0.5, loop=self.loop)
             proc.stdin.write(data)
             await proc.stdin.drain()