diff --git a/packages/playwright-test/src/cli.ts b/packages/playwright-test/src/cli.ts
index 540bf81ca6..27b6641539 100644
--- a/packages/playwright-test/src/cli.ts
+++ b/packages/playwright-test/src/cli.ts
@@ -178,6 +178,9 @@ async function runTests(args: string[], opts: { [key: string]: any }) {
 
 
 async function listTestFiles(opts: { [key: string]: any }) {
+  // Redefine process.stdout.write in case config decides to pollute stdio.
+  const write = process.stdout.write.bind(process.stdout);
+  process.stdout.write = (() => {}) as any;
   const configFileOrDirectory = opts.config ? path.resolve(process.cwd(), opts.config) : process.cwd();
   const resolvedConfigFile = Runner.resolveConfigFile(configFileOrDirectory)!;
   if (restartWithExperimentalTsEsm(resolvedConfigFile))
@@ -186,7 +189,7 @@ async function listTestFiles(opts: { [key: string]: any }) {
   const runner = new Runner({}, { defaultConfig: {} });
   await runner.loadConfigFromResolvedFile(resolvedConfigFile);
   const report = await runner.listTestFiles(resolvedConfigFile, opts.project);
-  process.stdout.write(JSON.stringify(report), () => {
+  write(JSON.stringify(report), () => {
     process.exit(0);
   });
 }