The Celtics  no longer are one of the toughest teams to play in the NBA, and president of basketball operations Danny Ainge does not appear content with that reality. After watching his team play mediocre defense over a 25-game sampling, Ainge on Thursday criticized the players’ collective play on The Big Show.
“We’ve got to prevent those runs by other teams and those droughts that we have at the offensive end and giving up so many lay-ins on the defensive end,” Ainge said. “There’s just no excuse for the way we’re playing. Yeah, you need to take time to find out who we are, but there’s no excuse for giving up 32 points in the paint in a half against Chicago, and there’s no excuse for giving up a 17-0 run to Cleveland.”
Last year’s Celtics delivered the template for a veteran NBA team looking to flip the proverbial switch in season. A five-game losing streak just before the All-Star break put the team’s record at 15-17. The Celtics went 24-10 after the break and eventually made a run to Game 7 of the Eastern Conference finals.
So why is Ainge sounding the alarm in December? From a distance, the Celtics’ 13-12 start to this season appears to follow the same trend — a veteran team going through the motions some nights, saving its collective legs for the second half and postseason.
A closer look proves that this year’s team is much different than last year’s team, and perhaps not due the same measure of patience from Ainge.
The most glaring difference between this year’s Celtics and last year’s is their inability to play strong team defense. Even when last year’s team slogged through the first half of the season, it ranked as one of the top two teams in the NBA defensively. Before the break, the 2011-12 C’s held opposing teams to 89.4 points per game and a field goal percentage of 41.9. Those numbers increased slightly after the break to 90.1 points per game and a field goal percentage of 42.1. Despite the slight increases, the Celtics still finished the season as the second-ranked team in the NBA in points allowed, behind only the Bulls, and they ranked first in opponents’ field goal percentage.
The Celtics’ most marked improvements last season took place on the offensive end. The C’s scoring average jumped from 89.4 before the break to 94.1 in the 34 games after. Their field goal percentage improved from 45.8 to 46.5.
The uptick in offensive statistics could be attributed to the improved conditioning of the veteran players, specifically Kevin Garnett  and Paul Pierce . Both players returned from the lockout needing time on the court to work themselves into peak condition. Garnett’s scoring average increased from 14.4 before the break to 17.0 after. Pierce’s scoring average jumped from 17.6 to 20.9. Conversely, Rajon Rondo ‘s scoring dipped from 14.8 before the break to 9.8 after. However, his assists average jumped from 9.5 to 13.2.
Simply put, Garnett and Pierce worked themselves into better condition throughout the season, and the ball found its way into their hands in the second half. As a result, the team was more efficient on offense. The Celtics took better shots earlier in their possessions, giving them more opportunities to score throughout the game.
This year’s team can not expect similar improvement based solely on improved offensive production. This year’s Celtics are a mediocre defensive team, ranking 16th in opposing points per game (97.7) and 13th in opposing field goal percentage (45.1). At no point last season did the Celtics’ defensive numbers approach that level of ineptitude.
On the other hand, Garnett and Pierce’s scoring averages are up from the first half of last season. Rondo’s scoring average is down, and his assists are up. The team’s offensive production has not been the problem, as once again the ball is finding its way into the scorers’ hands. In fact, the offensive production has improved since the second half of last season when the team went 24-10. During that stretch, the Celtics scored 94.1 points per game and shot 46.5 percent from the field. This season, the team has improved in both categories, averaging 97.3 points per game and 47.1 percent shooting from the field.
The rapid decline on the defensive end can not be attributed to a veteran team’s lack of focus or conditioning. Instead, the personnel — and specifically younger players such as Rondo, Courtney Lee  and Jeff Green  — have struggled to grasp defensive concepts. When Garnett is not on the floor, the Celtics become a bottom-tier team defensively.
Avery Bradley ‘s return in early January figures to bolster the defense, as he will immediately serve as the team’s best perimeter defender. But, remember, last year’s team was a top-tier defensive team in the first half when Bradley played limited minutes behind Ray Allen . From the sound of Ainge’s interview Thursday, he does not appear sold on the fact that one player will solve the team’s identity crisis. If the Celtics don’t show improvement on the defensive end before the trade deadline, expect Ainge to find better complementary pieces for Garnett.