I don't think I could put it any better than Scott Souza, so I won't even try. Here are some quotes from his article on April 18 that he linked to today, but you should read the whole thing.
...the one person who probably stands to take the biggest hit should the team underachieve remains with Doc Rivers - the coach who has yet to ever win a playoff series...
If the Celtics get into trouble this time around with arguably the most talent of any roster in the league, the still-skeptical legions who have somewhat-reluctantly given the coach his due following a 66-16 regular season will be poised to lead a chorus of critics against him....
With an 8-14 career playoff record, Rivers now has the chance to finally prove, once and for all, to doubters that he has "that feel" when it counts.
If he doesn't, no amount of spin will shield him this time around.
There's simply no question in my mind that if the Celtics lose this game tomorrow, Doc Rivers has to get fired. End of story. I'd much prefer that they win this game and move on. I very much hope that Doc can turn this around and do enough to win the title. But my confidence is shaken and I'm very close to hitching my wagon to the Bill Simmons Can Doc Express.
Has anyone ever finished 2nd in Coach of the Year voting and been fired in the same year? We're one loss away from seeing that happen.