diff --git a/packages/apollo-engine-reporting/src/plugin.ts b/packages/apollo-engine-reporting/src/plugin.ts
index a0179b30ef6..0c2a7e7eb6c 100644
--- a/packages/apollo-engine-reporting/src/plugin.ts
+++ b/packages/apollo-engine-reporting/src/plugin.ts
@@ -52,11 +52,9 @@ export const plugin = <TContext>(
           logger: requestContext.logger || logger,
         });
 
-      const metrics: NonNullable<typeof requestContext['metrics']> =
-        ((requestContext as Mutable<typeof requestContext>)
-          .metrics = requestContext.metrics || Object.create(null));
-
       treeBuilder.startTiming();
+
+      const metrics = requestContext.metrics;
       metrics.startHrTime = treeBuilder.startHrTime;
 
       if (requestContext.request.http) {