diff --git a/Library/Homebrew/cmd/test-bot.rb b/Library/Homebrew/cmd/test-bot.rb
index e228683a65..0be845b623 100644
--- a/Library/Homebrew/cmd/test-bot.rb
+++ b/Library/Homebrew/cmd/test-bot.rb
@@ -590,6 +590,11 @@ module Homebrew
           if bottle_step.passed? && bottle_step.has_output?
             bottle_filename =
               bottle_step.output.gsub(/.*(\.\/\S+#{bottle_native_regex}).*/m, '\1')
+            bottle_rb_filename = bottle_filename.gsub(/\.(\d+\.)?tar\.gz$/, ".rb")
+            bottle_merge_args = ["--merge", "--write", "--no-commit", bottle_rb_filename]
+            bottle_merge_args << "--tap=#{@tap}" if @tap
+            bottle_merge_args << "--keep-old" if ARGV.include? "--keep-old"
+            test "brew", "bottle", *bottle_merge_args
             test "brew", "uninstall", "--force", canonical_formula_name
             if unchanged_build_dependencies.any?
               test "brew", "uninstall", "--force", *unchanged_build_dependencies