LAKE BUENA VISTA, Fla. — Getting big leads has been relatively easy for the Boston Celtics in these Eastern Conference finals. This time, they also found a way to finish the job. And just like that, the East title series got a whole lot closer. Jaylen Brown scored 26 points, Jayson Tatum added 25 and the Celtics got right back into the East finals with a 117-106 victory over the Miami Heat in Game 3 on Saturday night.