diff --git a/Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean b/Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean
index f4250bbc6bda2..517b3998efaa0 100644
--- a/Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean
+++ b/Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean
@@ -666,6 +666,7 @@ theorem rightUnitor_monoidal (X₁ X₂ : C) :
   coherence
 #align category_theory.right_unitor_monoidal CategoryTheory.rightUnitor_monoidal
 
+set_option maxHeartbeats 400000 in
 theorem associator_monoidal (X₁ X₂ X₃ Y₁ Y₂ Y₃ : C) :
     tensor_μ C (X₁ ⊗ X₂, X₃) (Y₁ ⊗ Y₂, Y₃) ≫
         (tensor_μ C (X₁, X₂) (Y₁, Y₂) ▷ (X₃ ⊗ Y₃)) ≫ (α_ (X₁ ⊗ Y₁) (X₂ ⊗ Y₂) (X₃ ⊗ Y₃)).hom =