Forum:Stardust Assault vs Gorz the Emissary

Ok heres how the situation stands, I have a Stardust Assault on my side of the field and my opponent has a clear field. I do a direct attack and my opponent special summons Gorz. I know I cant negate the summon of Gorz with Stardust Assualt's effect because Gorz's effect happens before it hits the field. But then can I use Stardust's effect to negate the summon of a gorz tokken and destroy Gorz, since Gorz is on the field when that 2nd effect happens?