diff --git a/Sparkle/SUAppcastDriver.m b/Sparkle/SUAppcastDriver.m
index 9faea12b4..b55189f73 100644
--- a/Sparkle/SUAppcastDriver.m
+++ b/Sparkle/SUAppcastDriver.m
@@ -434,7 +434,10 @@ + (SUAppcastItem *)bestItemFromAppcastItems:(NSArray *)appcastItems getDeltaItem
     // Give the delegate a chance to provide a custom version comparator
     id<SPUUpdaterDelegate> updaterDelegate = _updaterDelegate;
     if ([updaterDelegate respondsToSelector:@selector((versionComparatorForUpdater:))]) {
-        comparator = [updaterDelegate versionComparatorForUpdater:_updater];
+        SPUUpdater *updater = _updater;
+        if (updater != nil) {
+            comparator = [updaterDelegate versionComparatorForUpdater:updater];
+        }
     }
 #pragma clang diagnostic pop