A championship’s value in combat sports is determined by the quality of the fighter who holds it and the quality of those vying for it. That’s what makes rivalries between the best fighters compelling before any punches are thrown: the converging focus on a title representing the most elite competitor in the division or the sport. Boston has a rich history with the world’s best. One need only look at the Celtics’ 17 NBA championships. The Ultimate Fighting Championship never had its shot to take center stage at the legendary Boston Garden, where the Celtics built their historic might.