Can Celtics' top-ranked defense stop red-hot Rockets?

BOSTON -- Boston Celtics guard Marcus Smart had already run the gamut of emotions after lacerating his right hand with one ill-advised, frustration-filled jab at a glass picture frame inside a Beverly Hills hotel in late January. But, sitting alone in his suburban Boston apartment and forced to watch his teammates stumble toward the All-Star break from afar, Smart was certain this was the worst feeling of all:

Helplessness.

With every defensive miscue -- and there were an astounding number of them -- Smart screamed at his television, then wondered how things might be different if he was on the court. After games, Smart called his teammates and tried to talk them through the slippage he was…