"Emotions got involved. I really didn't handle it the right way," Pierce said. "So, I'm just going to come out and apologize to my teammates, the coaching staff, the fans of Boston for what
happened last night."
Pierce and Rivers argued during Wednesday night's 101-100 win over Milwaukee.
"It was uncalled for," Pierce said. "I reacted at the moment. That's all it was. We handled it like men. I apologized to the team this morning and we move on."
Pierce said that he and Rivers had not talked things out, but the conversation doesn't need to be a long one.
"He's the coach," Pierce said. "Whatever he says goes, and that's it."
Pierce was pulled from the game against the Bucks with just over 4½ minutes to play and the Celtics holding a 92-91 lead. The star guard appeared agitated when Jiri Welsch came in for him. Pierce then got into a brief shouting match that Rivers ended by shouting, "You sit."
Rivers said he was upset because he didn't think Pierce was heading out quickly enough on the fast break. The coach, in his first year with the Celtics, said the argument "looked a lot worse
than it was."
"I sat him because I didn't think we were doing the right things," Rivers said. "I'd rather for him to be upset. I don't want a guy on my team who shows no passion. ... It's never personal."
The two chatted in the huddle during a timeout, and Pierce returned to hit a 3-pointer on Boston's first possession to give the Celtics a 97-93 lead with 2:40 to go.
"Regardless of what happens, I can't let it affect this team in winning and losing," Pierce said, adding that he wants to set a better example for the young players on the team.
"I was upset because I couldn't remember the last time I got snatched out of a game for something that was minor. But as a coach he makes the decisions and I've got to deal with it and move on."
Rivers said benching Pierce, the team's best player, was not intended as a message.
"I didn't intend it that way. It probably ended up that way," Rivers said. "I'm sure they see we'll take anybody out. Of all the times not to sit him it might have been that time. It was a tough
one. I'm sitting there taking Paul off the floor knowing there's a chance we could lose this game, but I thought that we had to make that call."