diff --git a/lib/roles/device.js b/lib/roles/device.js
index 161c3ebf..c24298f5 100644
--- a/lib/roles/device.js
+++ b/lib/roles/device.js
@@ -158,13 +158,12 @@ module.exports = function(options) {
       return devutil.ensureUnusedPort(adb, options.serial, 1080)
         .then(function(port) {
           var log = logger.createLogger('device:remote:monkey')
-          return adb.shellAsync(options.serial, [
+          return adb.shellAsync(options.serial, util.format(
               // Some devices fail without an SD card installed; we can
               // fake an external storage using this method
-              'EXTERNAL_STORAGE=/data/local/tmp'
-            , 'monkey'
-            , '--port', port
-            ])
+              'EXTERNAL_STORAGE=/data/local/tmp monkey --port %d'
+            , port
+            ))
             .then(function(out) {
               vitals.register('device:remote:monkey:shell', out)
               out.pipe(require('split')())