diff --git a/CHANGELOG.md b/CHANGELOG.md
index e35697f..442985c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## [Unreleased]
 
+- AR 6.1: fix - FrozenError: can't modify frozen object: []
 - Drop support for ActiveRecord older than 6.0.
 
 ## [1.4.4] - 2022-02-07
diff --git a/lib/baby_squeel/active_record/query_methods.rb b/lib/baby_squeel/active_record/query_methods.rb
index 267f69e..7e2dcc2 100644
--- a/lib/baby_squeel/active_record/query_methods.rb
+++ b/lib/baby_squeel/active_record/query_methods.rb
@@ -64,7 +64,9 @@ def construct_join_dependency(associations, join_type)
 
         # https://github.com/rails/rails/commit/c0c53ee9d28134757cf1418521cb97c4a135f140
         def select_association_list(*args)
-          args[0].extend(BabySqueel::ActiveRecord::QueryMethods::Injector6_1)
+          if args[0].any? { |join| join.is_a?(BabySqueel::Join) }
+            args[0].extend(BabySqueel::ActiveRecord::QueryMethods::Injector6_1)
+          end
           super *args
         end
       else
diff --git a/spec/integration/__snapshots__/rails_integration_spec.yaml b/spec/integration/__snapshots__/rails_integration_spec.yaml
index 13ae09d..fe8dfd4 100644
--- a/spec/integration/__snapshots__/rails_integration_spec.yaml
+++ b/spec/integration/__snapshots__/rails_integration_spec.yaml
@@ -5,3 +5,10 @@ test that plain rails still works joins and merge 1: SELECT "authors".* FROM "au
 test that plain rails still works left_joins 1: SELECT "posts".* FROM "posts" LEFT
   OUTER JOIN "posts" "parents_posts" ON "parents_posts"."id" = "posts"."parent_id"
   LEFT OUTER JOIN "authors" ON "authors"."id" = "posts"."author_id"
+test that plain rails still works joins includes 1: SELECT "posts"."id" AS t0_r0,
+  "posts"."title" AS t0_r1, "posts"."author_id" AS t0_r2, "posts"."published_at" AS
+  t0_r3, "posts"."view_count" AS t0_r4, "posts"."parent_id" AS t0_r5, "posts"."created_at"
+  AS t0_r6, "posts"."updated_at" AS t0_r7, "authors"."id" AS t1_r0, "authors"."name"
+  AS t1_r1, "authors"."age" AS t1_r2, "authors"."ugly" AS t1_r3, "authors"."created_at"
+  AS t1_r4, "authors"."updated_at" AS t1_r5 FROM "posts" INNER JOIN "authors" ON "authors"."id"
+  = "posts"."author_id"
diff --git a/spec/integration/rails_integration_spec.rb b/spec/integration/rails_integration_spec.rb
index a6dd3dc..418c3d3 100644
--- a/spec/integration/rails_integration_spec.rb
+++ b/spec/integration/rails_integration_spec.rb
@@ -12,4 +12,10 @@
 
     expect(relation).to match_sql_snapshot
   end
+
+  it 'joins includes' do
+    relation = Post.joins(:author).includes(:author).to_sql
+
+    expect(relation).to match_sql_snapshot
+  end
 end