diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 4306dd9266f..bfd636fa62a 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -220,18 +220,7 @@ class MergeRequest < ApplicationRecord
   end
 
   def rebase_in_progress?
-    (rebase_jid.present? && Gitlab::SidekiqStatus.running?(rebase_jid)) ||
-      gitaly_rebase_in_progress?
-  end
-
-  # TODO: remove the Gitaly lookup after v12.1, when rebase_jid will be reliable
-  def gitaly_rebase_in_progress?
-    strong_memoize(:gitaly_rebase_in_progress) do
-      # The source project can be deleted
-      next false unless source_project
-
-      source_project.repository.rebase_in_progress?(id)
-    end
+    rebase_jid.present? && Gitlab::SidekiqStatus.running?(rebase_jid)
   end
 
   # Use this method whenever you need to make sure the head_pipeline is synced with the
diff --git a/app/services/merge_requests/rebase_service.rb b/app/services/merge_requests/rebase_service.rb
index 8d3b9b05819..27c16ba1777 100644
--- a/app/services/merge_requests/rebase_service.rb
+++ b/app/services/merge_requests/rebase_service.rb
@@ -15,7 +15,8 @@ module MergeRequests
     end
 
     def rebase
-      if merge_request.gitaly_rebase_in_progress?
+      # Ensure Gitaly isn't already running a rebase
+      if source_project.repository.rebase_in_progress?(merge_request.id)
         log_error('Rebase task canceled: Another rebase is already in progress', save_message_on_model: true)
         return false
       end
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 53424204db7..d344a6d0f0d 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -3015,9 +3015,6 @@ describe MergeRequest do
       subject { merge_request.rebase_in_progress? }
 
       it do
-        # Stub out the legacy gitaly implementation
-        allow(merge_request).to receive(:gitaly_rebase_in_progress?) { false }
-
         allow(Gitlab::SidekiqStatus).to receive(:running?).with(rebase_jid) { jid_valid }
 
         merge_request.rebase_jid = rebase_jid
@@ -3027,42 +3024,6 @@ describe MergeRequest do
     end
   end
 
-  describe '#gitaly_rebase_in_progress?' do
-    let(:repo_path) do
-      Gitlab::GitalyClient::StorageSettings.allow_disk_access do
-        subject.source_project.repository.path
-      end
-    end
-    let(:rebase_path) { File.join(repo_path, "gitlab-worktree", "rebase-#{subject.id}") }
-
-    before do
-      system(*%W(#{Gitlab.config.git.bin_path} -C #{repo_path} worktree add --detach #{rebase_path} master))
-    end
-
-    it 'returns true when there is a current rebase directory' do
-      expect(subject.rebase_in_progress?).to be_truthy
-    end
-
-    it 'returns false when there is no rebase directory' do
-      FileUtils.rm_rf(rebase_path)
-
-      expect(subject.rebase_in_progress?).to be_falsey
-    end
-
-    it 'returns false when the rebase directory has expired' do
-      time = 20.minutes.ago.to_time
-      File.utime(time, time, rebase_path)
-
-      expect(subject.rebase_in_progress?).to be_falsey
-    end
-
-    it 'returns false when the source project has been removed' do
-      allow(subject).to receive(:source_project).and_return(nil)
-
-      expect(subject.rebase_in_progress?).to be_falsey
-    end
-  end
-
   describe '#allow_collaboration' do
     let(:merge_request) do
       build(:merge_request, source_branch: 'fixes', allow_collaboration: true)
diff --git a/spec/services/merge_requests/rebase_service_spec.rb b/spec/services/merge_requests/rebase_service_spec.rb
index ee9caaf2f47..7b8c94c86fe 100644
--- a/spec/services/merge_requests/rebase_service_spec.rb
+++ b/spec/services/merge_requests/rebase_service_spec.rb
@@ -25,7 +25,7 @@ describe MergeRequests::RebaseService do
   describe '#execute' do
     context 'when another rebase is already in progress' do
       before do
-        allow(merge_request).to receive(:gitaly_rebase_in_progress?).and_return(true)
+        allow(repository).to receive(:rebase_in_progress?).with(merge_request.id).and_return(true)
       end
 
       it 'saves the error message' do