if i was designing that new stadium i would have some sort of high strength tempered glass operated by a hydraulic system such that when they push the button the glass box emerges from the field turf and surrounds the goal posts so you - the trespassing fan - can still see them but you can't actually touch them.
Before you say anything, yes, i realize its obvious, event staff would have to screen for fans smuggling in those suction cup thingys that would allow them to scale the tempered glass enclosure but freedom aint free