diff --git a/scrapy/core/scraper.py b/scrapy/core/scraper.py
index 18095216e..84f9c958a 100644
--- a/scrapy/core/scraper.py
+++ b/scrapy/core/scraper.py
@@ -5,7 +5,7 @@ from twisted.python.failure import Failure
 from twisted.internet import defer
 
 from scrapy.utils.defer import defer_result, defer_succeed, parallel
-from scrapy.utils.misc import load_object
+from scrapy.utils.misc import load_object, arg_to_iter
 from scrapy.utils.signal import send_catch_log
 from scrapy.core.exceptions import IgnoreRequest, DropItem
 from scrapy.core import signals
@@ -131,7 +131,7 @@ class Scraper(object):
         return request.deferred.addCallback(self._iterable_spider_output)
 
     def _iterable_spider_output(self, result):
-        return [result] if isinstance(result, (BaseItem, Request)) else result
+        return [result] if isinstance(result, BaseItem) else arg_to_iter(result)
 
     def handle_spider_error(self, _failure, request, spider, propagated_failure=None):
         referer = request.headers.get('Referer', None)