diff --git a/scrapy/statscol.py b/scrapy/statscol.py
index cc627d57d..99fa6f841 100644
--- a/scrapy/statscol.py
+++ b/scrapy/statscol.py
@@ -37,7 +37,7 @@ class StatsCollector(object):
         self._stats.clear()
 
     def open_spider(self, spider):
-        self._stats = {}
+        pass
 
     def close_spider(self, spider, reason):
         if self._dump: