Paul Pierce , Ray Allen  and Kevin Garnett  all missed potential go-ahead buckets in the final 30 seconds, and the Celtics  suffered their worst loss of the season, 83-81, against a Bobcats team that traded its best player (Gerald Wallace ) and sat its next two most talented guys (Stephen Jackson  and Tyrus Thomas ) with injuries.
After blowing double-digit leads in both halves, the Celtics (50-21) still only trailed 82-81 with 27 seconds remaining. But Pierce (game-high 18 points) missed an ill-conceived, contested jump shot and Gerald Henderson  made 1-of-2 free throws to put the Bobcats (28-43) up two with 15 seconds left. Allen and Garnett each missed 3-point attempts in the finals seconds.
WHAT WENT WRONG
Not putting the game away early: After just eight minutes of action, the Celtics had pushed their lead to double digits, and it appeared as though Gino might make an appearance as early as the second quarter. But a lineup that included Glen Davis , Jeff Green , Delonte West  and Carlos Arroyo  let the Bobcats close the game to 25-19 by the end of the first quarter. Charlotte remained within single digits through halftime.
Not putting the game away late: Just as they did in the first half, the Celtics coughed up a double-digit lead — this time in the fourth quarter, with the starters on the floor. The Bobcats took the lead when Pierce missed a pair of free throws, Henderson grabbed an offensive rebound and laid it in as three C’s watched. Pierce then clanged a 3-point attempt off the backboard and Davis committed his sixth foul. That fourth-quarter stretch defined a game full of poor decisions, as the Celtics settled for jumpers offensively and lacked effort defensively.
Committing turnovers (again): The Celtics committed 18 turnovers in their 90-87 loss to the Grizzlies  on Wednesday, and on Friday they picked up where they left off — turning the ball over six times in the first 15 minutes. They finished with 17 turnovers that led to 13 Bobcats points.
WHAT WENT RIGHT
Getting Ray Allen involved early: The Celtics’ offense has struggled of late, especially in the first quarter, and Allen’s lack of touches has been part of that dilemma. Not Friday. And definitely not against the Bobcats. Allen took (and made) two 3-pointers in addition to drawing a pair of fouls that led to four free throws. All in all, he recorded 10 of the C’s 25 first-quarter points — the team’s best output for the opening 12 minutes in almost three weeks.
After that, you’d be hard-pressed to find anything else that went right for the Celtics.