diff --git a/src/Runner.Worker/ContainerOperationProvider.cs b/src/Runner.Worker/ContainerOperationProvider.cs
index c23858562..77e08b293 100644
--- a/src/Runner.Worker/ContainerOperationProvider.cs
+++ b/src/Runner.Worker/ContainerOperationProvider.cs
@@ -76,7 +76,7 @@ namespace GitHub.Runner.Worker
 
     public class ContainerOperationProvider : RunnerService, IContainerOperationProvider
     {
-        private IDockerCommandManager _dockerManager;
+        private IDockerCommandManager _dockerManager = null;
 
         public override void Initialize(IHostContext hostContext)
         {