diff --git a/azure-pipelines-ci.yml b/azure-pipelines-ci.yml
index f045c52c1c5..22675aa6e1a 100644
--- a/azure-pipelines-ci.yml
+++ b/azure-pipelines-ci.yml
@@ -19,7 +19,7 @@ jobs:
   pool:
     vmImage: 'ubuntu-latest'
   strategy:
-    maxParallel: 2
+    maxParallel: 1
     matrix:
       Python35:
         python.version: '3.5'