diff --git a/ext/TensorKitChainRulesCoreExt.jl b/ext/TensorKitChainRulesCoreExt.jl
index bf7c5526..a5342483 100644
--- a/ext/TensorKitChainRulesCoreExt.jl
+++ b/ext/TensorKitChainRulesCoreExt.jl
@@ -178,7 +178,7 @@ function svd_rev(U::AbstractMatrix, S::AbstractMatrix, V::AbstractMatrix, ΔU, 
     F = _invert_S²(S, tol)
     S⁻¹ = pinv(S; atol=tol)
 
-    term = Diagonal(diag(ΔS))
+    term = ΔS isa ZeroTangent ? ΔS : Diagonal(diag(ΔS))
 
     J = F .* (U' * ΔU)
     term += (J + J') * S