Apart from the excellent advice about using a long line, I have a couple of suggestions which I hope you'll find useful.
Take 2 balls out with you instead of just the one. That way, you can teach him to bring back the ball he has so you can throw the ball you have, kind of swapping. Just make sure you at least have your foot on the ball he's given back before throwing yours or you may find (as I have in the past lol) that the dog will quickly snatch up the ball and end up with both!
Obviously the problem with coming back has become a very rewarding game for your boy. I would firstly never engage in a chase game, after all, they can run much faster and we wouldn't have a chance! Two things I would try are sitting on the floor, no eye contact with the dog & look down as though you're interested in something. Otherwise, crouch down, back to the dog and scratch the ground. 9 out of 10 times their curiosity will win over & they'll come to investigate this thing you're more interested in! If mine ignore me, a "see ya" and an about turn by me will result in 3 goldens by my side. I will walk away and hide behind a tree if necessary so they have to find me lol!
My dogs would often head off towards the sea when I took them to the beach, annoyingly usually at the end of our walk! Bearing in mind when the tide is out there are vast mud flats, not ideal! I would immediately turn my back walk in the opposite direction then crouch & scratch the floor. This almost always worked and usually before they hit the mud, & 3 retrievers could be seen hurtling the few hundred metres back to me. I never called or made a sound, just something which worked wonders for me.
The only other thing I can suggest is that you take him on some more structured "walks". I try to take mine to many different environments, some wide open spaces where they can run, jump and chase each other
, and some other places, more enclosed where there are lots of trees and smells. They don't hurtle about quite so much, but is a very enriching walk for them, and tires them out just as much. Just to throw a ball time after time isn't very stimulating for them tbh, they need the stimulation of a "hunt" which is effectively what a walk is all about.
Mine love balls I'm not against them at all, but I don't use them on every walk & only then for a few throws at a time, then they go in the pocket whereby the dogs will immediately switch into sniffing & interacting with each other mode.
Good luck with your boy, they can be a challenge!!