With or without Kevin Garnett  and with or without the high-scoring Kevin Martin  in the game for the Rockets, Rivers felt his team was capable of a whole lot better than they showed in a 108-102 loss at TD Garden.
But the trademark defense that has been a staple of these championship-driven Celtics has not been there in the last week, and Rivers fears that if they start falling in love with scoring instead of doing the dirty work, they’ll lose something a lot more important – home court advantage in the NBA playoffs .
Don’t look now but not only are the Spurs putting some distance between themselves and the Celtics – who fell to 28-9 – but the Miami Heat  have, in the space of about three weeks, caught up to them with a torrid winning streak.
If the Celtics aren’t careful, they not only might have to win an NBA Finals  Game 7 on the road like last year in LA but they may have to do the same thing against Miami just to get there.
“To me, you can see them thinking about the individual game and not the ramifications of the entire season,” Rivers said of his team. “And playing Game 7 on the road. And hell, not just in the Finals if you make it there, but in the playoffs. In the East, which is going to be difficult. This year’s not like last year where you can coast. You don’t have home court this year, you could go home.
‘You know especially at home, I think we need to really take advantage of games where their best player isn’t playing, guys coming off injury,” captain Paul Pierce  added. “These games mean a lot down the road, and but at the same time, they’re going to suit up and play, and we got to understand that nothing is given to us cause their down a man, or they’ve been struggling for most of the year. We got to put our work boots on and come with our A game, we’re not taking advantage of this, there are a lot of games that we’re letting slip away that we’re supposed to win’
As for Monday, they allowed the Rockets to make 21-of-34 shots in the second half on Boston’s famed but now not-so-feared parquet. That’s better than 60 percent. That’s very alarming in Rivers’ world.
“We just weren’t ready,” Rivers lamented afterward. “I told our guys I thought overall it was probably our worst defensive effort in three, four years as far as overall effort. You know ‘ and it’s on the starters, it’s not on the second unit ‘ I thought our second unit actually got us back in the first half and in the second half, and all they did was came in and played hard. They played aggressive. And I also told our starters that when we’re down men like we are with Perk [Kendrick Perkins ] and Delonte [West ] and Kevin out, our second unit needs your help.
“They need you to play well, to give them a cushion. It shouldn’t be the other way around. And so, just a really disappointing game for us. You know, a home game without one of their best scorers ‘ I don’t know if he’s their best player, but he’s their best scorer. We’ve lost to Oklahoma City at home, without two of their best players.”
As a matter of record, 28-9 sounds really good but then again the Celtics have lost to Oklahoma City at home without Kevin Durant , the Detroit Pistons  on the road and now, the Rockets without their leading scorer – Kevin Martin.
“So you look at some of our other losses, record-wise, you know it’s mental,” Rivers said. “That’s a mental mindset and it starts with me. I’ve got to somehow figure out a way of getting them to see the urgency of the whole season and not the single game.”
So was it the Celtics’ worst D of the season?
‘I wont say it’s the worst, I thought there was just a stretch where we just couldn’t stop anybody,” Ray Allen  said. “I cant say that, we knew that they were going to run. I blame the starting five because we gave them too much confidence early. That fourth quarter stretch came where it seemed like they hit everything. Where guy’s weren’t where they needed to be, or in position, rotation, moving the ball around. They scored and then we did a terrible job of rebounding. And times we did stop them, they got their hands on the ball and tipped it back out or tipped it into the rim. Those are the things early in the game we got to put a lid on.’