diff --git a/Library/Homebrew/extend/pathname.rb b/Library/Homebrew/extend/pathname.rb
index 1436e2e8e5..8398bb17d0 100644
--- a/Library/Homebrew/extend/pathname.rb
+++ b/Library/Homebrew/extend/pathname.rb
@@ -114,18 +114,18 @@ class Pathname
     end
 
     # github tarballs, like v1.2.3
-    %r[github.com/.*/tarball/v?((\d\.)+\d+)$].match to_s
-    return $1 if $1
+    %r[github.com/.*/(zip|tar)ball/v?((\d\.)+\d+)$].match to_s
+    return $2 if $2
 
     # dashed version
     # eg. github.com/isaacs/npm/tarball/v0.2.5-1
-    %r[github.com/.*/tarball/v?((\d\.)+\d+-(\d+))$].match to_s
-    return $1 if $1
+    %r[github.com/.*/(zip|tar)ball/v?((\d\.)+\d+-(\d+))$].match to_s
+    return $2 if $2
 
     # underscore version
     # eg. github.com/petdance/ack/tarball/1.93_02
-    %r[github.com/.*/tarball/v?((\d\.)+\d+_(\d+))$].match to_s
-    return $1 if $1
+    %r[github.com/.*/(zip|tar)ball/v?((\d\.)+\d+_(\d+))$].match to_s
+    return $2 if $2
 
     # eg. boost_1_39_0
     /((\d+_)+\d+)$/.match stem