diff --git a/app/workers/update_merge_requests_worker.rb b/app/workers/update_merge_requests_worker.rb
index 150788ca611..89ae17cef37 100644
--- a/app/workers/update_merge_requests_worker.rb
+++ b/app/workers/update_merge_requests_worker.rb
@@ -2,10 +2,6 @@ class UpdateMergeRequestsWorker
   include Sidekiq::Worker
   include DedicatedSidekiqQueue
 
-  def metrics_tags
-    @metrics_tags || {}
-  end
-
   def perform(project_id, user_id, oldrev, newrev, ref)
     project = Project.find_by(id: project_id)
     return unless project
@@ -13,11 +9,6 @@ class UpdateMergeRequestsWorker
     user = User.find_by(id: user_id)
     return unless user
 
-    @metrics_tags = {
-      project_id: project_id,
-      user_id: user_id
-    }
-
     MergeRequests::RefreshService.new(project, user).execute(oldrev, newrev, ref)
   end
 end
diff --git a/changelogs/unreleased/.yml b/changelogs/unreleased/.yml
new file mode 100644
index 00000000000..acf0bb80c72
--- /dev/null
+++ b/changelogs/unreleased/.yml
@@ -0,0 +1,5 @@
+---
+title: Remove update merge request worker tagging.
+merge_request:
+author:
+type: removed
diff --git a/lib/gitlab/metrics/sidekiq_middleware.rb b/lib/gitlab/metrics/sidekiq_middleware.rb
index 55c707d5386..df4bdf16847 100644
--- a/lib/gitlab/metrics/sidekiq_middleware.rb
+++ b/lib/gitlab/metrics/sidekiq_middleware.rb
@@ -11,8 +11,6 @@ module Gitlab
           # Old gitlad-shell messages don't provide enqueued_at/created_at attributes
           trans.set(:sidekiq_queue_duration, Time.now.to_f - (message['enqueued_at'] || message['created_at'] || 0))
           trans.run { yield }
-
-          worker.metrics_tags.each { |tag, value| trans.add_tag(tag, value) } if worker.respond_to?(:metrics_tags)
         rescue Exception => error # rubocop: disable Lint/RescueException
           trans.add_event(:sidekiq_exception)
 
diff --git a/spec/lib/gitlab/metrics/sidekiq_middleware_spec.rb b/spec/lib/gitlab/metrics/sidekiq_middleware_spec.rb
index 6d69b5305d2..ae1d8b47fe9 100644
--- a/spec/lib/gitlab/metrics/sidekiq_middleware_spec.rb
+++ b/spec/lib/gitlab/metrics/sidekiq_middleware_spec.rb
@@ -4,32 +4,40 @@ describe Gitlab::Metrics::SidekiqMiddleware do
   let(:middleware) { described_class.new }
   let(:message) { { 'args' => ['test'], 'enqueued_at' => Time.new(2016, 6, 23, 6, 59).to_f } }
 
-  def run(worker, message)
-    expect(Gitlab::Metrics::BackgroundTransaction).to receive(:new)
-      .with(worker.class)
-      .and_call_original
-
-    expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:set)
-      .with(:sidekiq_queue_duration, instance_of(Float))
-
-    expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:finish)
-
-    middleware.call(worker, message, :test) { nil }
-  end
-
   describe '#call' do
-    let(:test_worker_class) { double(:class, name: 'TestWorker') }
-    let(:worker) { double(:worker, class: test_worker_class) }
-
     it 'tracks the transaction' do
-      run(worker, message)
+      worker = double(:worker, class: double(:class, name: 'TestWorker'))
+
+      expect(Gitlab::Metrics::BackgroundTransaction).to receive(:new)
+        .with(worker.class)
+        .and_call_original
+
+      expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:set)
+        .with(:sidekiq_queue_duration, instance_of(Float))
+
+      expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:finish)
+
+      middleware.call(worker, message, :test) { nil }
     end
 
     it 'tracks the transaction (for messages without `enqueued_at`)' do
-      run(worker, {})
+      worker = double(:worker, class: double(:class, name: 'TestWorker'))
+
+      expect(Gitlab::Metrics::BackgroundTransaction).to receive(:new)
+        .with(worker.class)
+        .and_call_original
+
+      expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:set)
+        .with(:sidekiq_queue_duration, instance_of(Float))
+
+      expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:finish)
+
+      middleware.call(worker, {}, :test) { nil }
     end
 
     it 'tracks any raised exceptions' do
+      worker = double(:worker, class: double(:class, name: 'TestWorker'))
+
       expect_any_instance_of(Gitlab::Metrics::Transaction)
         .to receive(:run).and_raise(RuntimeError)