Rookie Jayson Tatum helps Celtics regain control of series, but can he keep it up?

Sometimes you forget what you are looking at in Jayson Tatum, a sinewy 6-foot-8, 205-pound forward with a scorer’s touch. You forget that he’s 20, a year removed from playing in the NCAA tournament, two years from high school, when he was a math-taking student with a pair of Air Jordans — or whatever