Goldo could stop time, and Vegeta killed him. Time manipulation probably isn't a problem for Goku.>Erase
It has to touch something to make it disappear, right? Goku is capable of FTL travel.>Create
Create only works at night. And if it's night, he can just fly to where it's day.>Change
Goku's been through this when he fought Ginyu, and he won the day. I doubt Sakura could fare any better with a similar strategy.>Twin
What could Sakura possibly duplicate to threaten Goku? I mean, if nothing she can dish out even fazes him, what difference does two of something make?
Also, Sakura isn't exactly quick on the draw. Goku could kill her a thousand times in the time it takes for her to say "Windy!"