diff --git a/lib/gitlab/blame.rb b/lib/gitlab/blame.rb
index ac39daf375f66dae2aa30138d3cbb1b7124e1586..c2ddca469b90bc7deed4e0b2d1f3b3360cb526a3 100644
--- a/lib/gitlab/blame.rb
+++ b/lib/gitlab/blame.rb
@@ -29,7 +29,7 @@ def groups(highlight: true)
           current_group = { commit: commit, lines: [], previous_path: previous_path, span: span, lineno: i + 1 }
         end
 
-        current_group[:lines] << (highlight ? highlighted_lines[i].html_safe : line)
+        current_group[:lines] << (highlight && highlighted_lines[i] ? highlighted_lines[i].html_safe : line)
 
         prev_sha = commit.sha
         i += 1
diff --git a/spec/lib/gitlab/blame_spec.rb b/spec/lib/gitlab/blame_spec.rb
index bfe2b7d1360a5a7855372778ad28854c39904456..493fe453f850d2b8ba2a1540223ecba960e040b4 100644
--- a/spec/lib/gitlab/blame_spec.rb
+++ b/spec/lib/gitlab/blame_spec.rb
@@ -67,6 +67,17 @@
           expect(groups[1][:lines][0]).to match(/LC4.*Popen/)
           expect(groups[1][:lines][1]).to match(/LC5.*extend/)
         end
+
+        context 'when highlighed lines are misaligned' do
+          let(:raw_blob) { Gitlab::Git::Blob.new(data: "Test\r\nopen3", path: path, size: 6) }
+          let(:blob) { Blob.new(raw_blob) }
+
+          it 'returns the correct lines' do
+            expect(groups.count).to eq(2)
+            expect(groups[0][:lines][0]).to match(/LC1.*Test/)
+            expect(groups[0][:lines][1]).to match(/LC2.*open3/)
+          end
+        end
       end
     end