When Ray Allen's cast at the buzzer of Sunday's showdown between the Boston Celtics and the Los Angeles Lakers proved errant, it crystallized the perception that the two teams are heading in opposite directions. While the Lakers won their fourth consecutive game, the Celtics suffered their third loss in as many matchups against other contenders over the last four days and dropped to 6-11 since beating the Orlando Magic on Christmas Day.
In the wake of that stretch, experts are already beginning to eulogize Boston's chances of reclaiming the NBA championship. That might be a little on the pessimistic side, but the numbers certainly suggest reasons to worry in Beantown.
The Celtics' season was divided by the hyperextended right knee suffered by All-Star forward Kevin Garnett on Dec. 27. Boston went 4-6 during the 10 games Garnett missed, and his return to the lineup has failed to provide the boost the Celtics were hoping to get from him. Garnett has looked a step slow, most notably on the final defensive play of Thursday's loss at Orlando when Magic forward Rashard Lewis beat him off the dribble to score the game-winning basket.
Here's a look at Boston's season broken down into three segments--prior to Garnett's injury, during his absence and since his return.
Period ORtg DRtg AOff ADef ADiff
Garnett healthy 111.4 100.4 +2.8 +7.1 +7.7
Garnett injured 108.0 110.2 -1.9 -0.7 -1.2
Garnett return 103.5 103.6 -3.0 +7.1 +1.9
Garnett's impact is most obvious looking at the Boston defense. The Celtics, leading the league in Defensive Rating at the time of his injury, were below average at the defensive end during the 10 games Garnett missed. However, they've picked up where they left off over the last five games even with Garnett at less than 100 percent, holding teams the same 7.1 points per 100 possessions below their season-long Offensive Rating they managed through Dec. 28.
The more surprising numbers are on offense. The Celtics did see their scoring drop off when Garnett was out of the lineup (hidden slightly by the fact that they faced a weaker set of defenses but stronger offenses in those 10 games, as the adjusted numbers show), but Boston's Offensive Rating has continued to drop over the last five games. It was 43.9 percent effective shooting and 17 turnovers that cost the Celtics last Friday in Atlanta, and the loss to the Lakers was essentially a defensive struggle (Boston scored at a rate of 103.7 points per 100 possessions, the Lakers 103.4).
In part, Garnett has not been himself on offense. He's used possessions at a rate slightly below average since coming back, is shooting 46.9 percent from the field and has just two offensive rebounds in five games. If Garnett hasn't helped, however, he hasn't exactly hurt either, and the issues go far beyond him.
The biggest problem has been turnovers. Actually, the Celtics have long struggled to take care of the basketball, and their turnover rate before Garnett's injury (14.6 percent of their possessions) put them 28th in the league. Over the last month, Boston has gone from bad to inexplicably awful, coughing the ball up on 16.2 percent of possessions. No team in the league is worse than 15.2 percent over the course of the season. Paul Pierce has especially seen his turnovers skyrocket since returning from his own knee injury. He's turned the ball over on 16.9 percent of his possessions, up from 12.6 percent in the season's first two months.
Beyond the turnovers, the Celtics aren't shooting the ball nearly as well as they need to succeed. Last spring, Boston overcame Garnett's injury to win a playoff series and force Game 7 against the eventual Eastern Conference champion Orlando Magic by improving its offense on the strength of super-accurate three-point shooting, hitting 39.5 percent for the season. That kind of marksmanship hasn't been there this time around. The Celtics improved their accuracy beyond the arc slightly from 34.8 percent to 35.8 percent in the 10 games Garnett missed, but they've hit triples at just a 33.7 percent clip in the last five games.
The biggest culprit here has been Allen. Over the last eight games, he has been mired in one of the deepest shooting slumps of his career, shooting 10-of-42 (23.8 percent) from beyond the arc. Of course, the last time Allen slumped so badly was the 2008 postseason, when he followed it up by playing fantastic basketball in Boston's NBA Finals win. This cold snap has a greater feeling of permanence. Allen is shooting a career-low 33.9 percent from downtown this season, and has seen his True Shooting Percentage slip even as he plays a smaller role in the Celtics' offense. Both PER and WARP suggest Allen has been a below-average contributor over the course of the season.
Given Allen's slump, last week's trade rumor from CSN New England that the Golden State Warriors would offer Boston Monta Ellis in exchange for Allen managed not to entirely ring hollow. Ellis, a poor outside shooter whose strengths duplicate those of Celtics point guard Rajon Rondo, is the wrong fit, but if the right deal came along for Allen Boston might have to give serious thought to getting younger at the position. Allen no longer deserves to be considered untouchable.
The high-profile nature of the Celtics' last three games, which included games on TNT and ABC, certainly didn't help the public perception of where Boston stands. Losing three close games surely made the Celtics look worse than they are, and the outcry would not be nearly the same if Bryant's shot had gone in or Rasheed Wallace had stepped up to stop Lewis' late drive in Orlando. By the numbers, playing the Magic to essentially a draw on the road was a solid performance for the Celtics, and they were above-average against the Lakers as well.
Still, these are the games Boston is going to eventually have to win to reach its goals this season. To do that, the Celtics are going to have to solve some issues on the offensive end of the floor. Getting Allen going and the turnovers to the point where they are at least manageable, as they were early in the season, will go a long ways toward rehabilitating Boston's image and restoring talk of hanging an 18th banner at the TD Garden.
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Kevin Pelton is an author of Basketball Prospectus.
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