Missed opportunities add up to loss

Why did the Boston Celtics lose to the Dallas Mavericks on Monday night at the American Airlines Center? The following list of second-chance opportunities generated by individual offensive rebounds sums it up pretty well (player with offensive rebound and time remaining, then the ensuing result):

1. Paul Pierce (11:15, 1st) -- After foul, Pierce misses 21-foot jumper
2. Kevin Garnett (10:57, 1st) -- Pierce misses 25-foot 3-pointer
3. Rajon Rondo (9:56, 1st) -- Rondo misses tip

4. Jermaine O'Neal (6:01, 1st) -- O'Neal misses 10-foot jumper

5. Garnett (5:58, 1st) -- Allen misses layup (Tyson Chandler block)
6. Garnett (5:54, 1st) -- Garnett misses 6-foot jumper

7. O'Neal (5:41, 1st) -- O'Neal turnover (Jason Kidd steal)

8. O'Neal (5:31, 2nd) -- O'Neal misses tip-in

9. Rondo (2:14, 2nd) -- O'Neal misses 12-foot jumper

10. Garnett (2:08, 2nd) -- Garnett misses tip-in

11. Rondo (2:06, 2nd) -- Rondo turnover

12. Allen (7:24, 3rd) -- Allen converts layup
13. Rondo (0:54, 4th) -- Garnett misses 4-foot jumper

14. Allen (0:02, 4th) -- After foul, Garnett misses 21-foot jumper

The Celtics hauled in 14 offensive rebounds* and generated a measly third-quarter layup out of it. No fouls drawn, no free throws attempted. And that's not a reflection of the referees, who certainly put their whistles away for much of the night but never appeared to miss anything too egregious (and were fair to both sides).

Boston generated only seven free-throw attempts overall for the game and much of that can be traced to a jump-shot-happy squad that seemed unwilling -- or unable -- to get to the rim. As coach Doc Rivers suggested afterward, Boston seemed content to stand around on offense, hold the ball, and fire away when the shot clock ran low. The Celtics hoisted a staggering 91 shots in 91 possessions (by comparison, Dallas took only 66 shots on the same amount of possessions) and settled for 31 mid-range jumpers (16-to-23 feet) and anther 18 shots from inside of 10 feet (but away from the rim).

During Boston's five-game winning streak, the Celtics were 57 of 136 from mid-range, a solid 42 percent. On Monday night, the team hit
12 of 31 attempts from that range, a mere 38.7 percent.

Those 18 shots attempted inside of 10 feet were curious, too. The Celtics hadn't taken more than 11 shots from that range in a game this season, but essentially doubled their season average in attempts (hitting only five of them, for a woeful 27.8 percent shooting). Chief
offender: Garnett, who was 1-of-6 and seemingly got forced further away from the rim than he might normally like.

The Celtics certainly failed to execute late in the game and that cost them in the final 73 seconds, when a poor defensive rotation allowed Jason Terry to hit a game-tying 3-pointer, and an ill-considered switch allowed Dirk Nowitzki to drill a go-ahead jumper over undersized Glen Davis with 17 seconds to play.

You can't fault Rajon Rondo's 3-point attempt; it was the right shot as Boston's offense again seemed unwilling to create space through off-ball movement. The last gasp after Ray Allen hauled in the offensive rebound, again, seemed poorly conceived -- or poorly executed -- but at least the Celtics got a shot off (something they haven't always done).

No, the Celtics had opportunities throughout the night on Monday and did little to take advantage of them. Weary on the second night of a back-to-back, they used much of their energy in a third-quarter rally and settled for poor looks the rest of the way. In fact, Boston took only one shot at the rim over the final seven minutes of play (and, not surprisingly, it led to three of only seven points during that span). Check out the following shot log for those final seven minutes:

6:56 -- Marquis Daniels misses 4-foot jumper (blocked)
5:56 -- Rondo misses 17-foot jumper
5:26 -- Paul Pierce misses 19-foot jumper
4:54 -- Pierce misses 13-foot jumper
4:22 -- Allen misses 18-foot jumper
3:47 -- Glen Davis misses 21-foot jumper
3:13 -- Rondo converts layup and free throw
2:31 -- Rondo converts 20-foot jumper
1:58 -- Pierce convets 16-foot jumper
1:27 -- Pierce misses 5-foot jumper
0:55 -- Allen misses 18-foot jumper
0:37 -- Garnett misses 4-foot jumper
0:03 -- Rondo misses 24-foot jumper
0:01 -- Garnett misses 23-foot jumper

The Celtics were 3-of-14 shooting during that stretch, going 1 of 8 for shots over 13 feet.
Maybe Rivers said it best before Sunday's game in Oklahoma City, noting that the Celtics have plenty of room for improvement despite a solid record. On Monday, playing one of the Western Conference's top squads on the second night of a back-to-back, Boston did all it could to fumble the game away, and still gave itself a chance to win at the end. There's room for improvement, but take solace in the fact that, if Boston had simply taken advantage of its opportunities throughout the game, it would have escaped with a victory.

* Note: Boston also got credited with three team offensive rebounds.

Here's the breakdown on those:

1. Team (6:18, 1st) -- C's regain possession after DeShawn Stevenson blocks Ray Allen. Stevenson is whistled for technical foul after demonstrative outburst (Allen hits the freebie), then Garnett misses a 19-foot jumper on the possession.
2. Team (10:03, 2nd) -- Nate Robinson converts 3-pointer

3. Team (0:00, 2nd) -- End of first half

Chris Forsberg is the Celtics reporter for ESPNBoston.com. Follow him on Twitter.