diff --git a/spec/commands/update_spec.rb b/spec/commands/update_spec.rb
index a2842f099..21e2ae2d5 100644
--- a/spec/commands/update_spec.rb
+++ b/spec/commands/update_spec.rb
@@ -640,7 +640,7 @@ RSpec.describe "bundle update --bundler" do
       source "file:#{gem_repo4}"
       gem "rack"
     G
-    lockfile lockfile.sub(Bundler::VERSION, "1.0.0")
+    lockfile lockfile.sub(/(^\s*)#{Bundler::VERSION}($)/,'\11.0.0\2')
 
     FileUtils.rm_r gem_repo4