diff --git a/experimental/Schemes/src/elliptic_surface.jl b/experimental/Schemes/src/elliptic_surface.jl
index 03863aee86a0..b2dee2971049 100644
--- a/experimental/Schemes/src/elliptic_surface.jl
+++ b/experimental/Schemes/src/elliptic_surface.jl
@@ -1653,7 +1653,7 @@ function transform_to_weierstrass(g::MPolyRingElem, x::MPolyRingElem, y::MPolyRi
     new_trans = MapFromFunc(F, F, f->begin
                                 switch_num = switch(numerator(f))
                                 switch_den = switch(denominator(f))
-                                interm_res = trans(F(switch_num))//trans(F(switch(den)))
+                                interm_res = trans(F(switch_num))//trans(F(switch_den))
                                 num = numerator(interm_res)
                                 den = denominator(interm_res)
                                 switch(num)//switch(den)