Just so people are aware, Ainge doesn't need to make a trade to fit Hayward. He could simply stretch Smart, and that, combined with releasing Mickey and stashing Yabusele (or renouncing him) would be sufficient. And Smart wouldn't clear waivers, so there'd be no long-term detriment to the cap.
Ainge will get something for one of them, because he doesn't need to make a trade. He needs to clear one off the roster, but trading isn't the only method.