Bench Bass and Pierce, and sort out what's left. Just don't let either one of them on the court for a while.
Bass has literally NO basketball skills beyond a slow, wide open jump shot, and Pierce's have seemingly evaporated over the past three months. And they both suffer from ADD - Bass from Attention Deficit Disorder and Pierce from Arrogant Deficit Disorder.
See if the guys who stretched the lead can sustain it without any "help" from these two starters. Can they play together, you know, like run, cut, dribble, pass, defend, rebound, etc., all those basketball kinds of things we DO NOT SEE when Pierce and Bass are on the court?
If the results are better, or even the same, keep them both on the bench, or trade both of them for Gay, or Gasol, or Z-Bo, or Lil' Nate, anybody!