[Bisjoe]

I would fill the pipe with sand, and if it becomes a problem, you could always protect it with concrete over the pipe, a lot easier to do. We used to use rebar to anchor the big full sized soccer goals, and we would use 3’ length, and drive them nearly all the way into the ground at a very sharp angle, then weld to the bottom of the frame. On the sides, you could just drill holes at an angle through the pipes and drive in 2’ pieces. Bending it into a U shape is not easy and the can still pull out if vertical, 90 degrees to the ground.