diff --git a/buildkite/pipelines/bazelci.py b/buildkite/pipelines/bazelci.py
index eb8c8ed..7cce3f4 100644
--- a/buildkite/pipelines/bazelci.py
+++ b/buildkite/pipelines/bazelci.py
@@ -159,7 +159,7 @@
      - \"os={2}\"""".format(label, "{0} --platform={1} {2} ".format(runner_command(platform), platform, http_config_flag(http_config)), platform)
 
 def runner_command(platform):
-    return "python3 bazelci.py --runner=true"
+    return "python3.6 bazelci.py --runner=true"
 
 def http_config_flag(http_config):
     if http_config is not None: