The darkest hour is just before the dawn. After a 1-4 west coast trip ended with a familiar refrain in Portland--dig a deep first half hole, play desperately to catch up, and lose in the final two minutes--this seems to be rock bottom for a Celtics team that was aspiring to raise a championship trophy in July. Gone are the familiar excuses of “it’s early” and “guys are coming back from injury.” With a 7-6 record, Toronto and Milwaukee boat racing out to 12-1 and 10-3 respectively, and the 76ers trading for Jimmy Butler on Saturday, the time is now.