diff --git a/packages/playwright/src/reporters/teleEmitter.ts b/packages/playwright/src/reporters/teleEmitter.ts
index eadd2b05a5..76fc1490a6 100644
--- a/packages/playwright/src/reporters/teleEmitter.ts
+++ b/packages/playwright/src/reporters/teleEmitter.ts
@@ -256,7 +256,7 @@ export class TeleReporterEmitter implements ReporterV2 {
       id: (step as any)[this._idSymbol],
       duration: step.duration,
       error: step.error,
-      attachments: step.attachments.map(a => result.attachments.indexOf(a)),
+      attachments: step.attachments.length ? step.attachments.map(a => result.attachments.indexOf(a)) : undefined,
       annotations: step.annotations.length ? step.annotations : undefined,
     };
   }
diff --git a/packages/playwright/src/worker/testTracing.ts b/packages/playwright/src/worker/testTracing.ts
index 15bb17db06..e154d6a649 100644
--- a/packages/playwright/src/worker/testTracing.ts
+++ b/packages/playwright/src/worker/testTracing.ts
@@ -278,6 +278,8 @@ export class TestTracing {
 }
 
 function serializeAttachments(attachments: Attachment[]): trace.AfterActionTraceEvent['attachments'] {
+  if (attachments.length === 0)
+    return undefined;
   return attachments.filter(a => a.name !== 'trace').map(a => {
     return {
       name: a.name,