Perhaps its D poor writing Looking at it now it seems that I must have been tired when I finished the massive edit I was making I meant under the net cord not under the net and through the net doesnt even make sense to me and I wrote it because that is supposed to be impossible and the rules say that it cant touch the net anyway Just as a reference rule d which I was reading at the time says It is a good return if The ball passes under the net cord between the singles stick and the adjacent net post without touching either net net cord or net post and hits the ground in the correct court hopefully my new phrasing is in agreement with that now Anyway thanks for getting me to reexamine this as it was a rather embarrassing mistake of mine I wish more people actually paid attention to these basic tennis articles like you did