In the last game before the All-Star break, the Celtics gave up 119 points in a loss to Oklahoma City, their fifth straight loss. Boston limped into the break with a 15-17 record and looked as if it would spend the second half angling for a low seed in the East, a prize that promised a probable first-round annihilation at hands of Miami or Chicago. Boston's 96.4 defensive rating (points per 100 possessions) ranked fourth in the league, but wasn't enough to prop up the 23rd-ranked offense.
The post break schedule didn't promise to do the Celtics any favors. Boston was looking at a stretch of 12 out of 17 games on the road that included an eight-game trip. Pundits like me were calling for team president Danny Ainge to explore breaking up his veteran core at the trade deadline if the right opportunities came along. The current era of Celtics basketball was teetering on the edge of extinction.
The Celtics won five in a row and six of seven after the break, and the trade deadline came and went with the team's big four of Rajon Rondo, Ray Allen, Paul Pierce and Kevin Garnett still intact. The success has continued, as Boston has gone 17-7 overall since that Feb. 22 nadir and passed Philadelphia for the lead in the Atlantic Division. The Celtics have put up an NBA-best 94.5 defensive rating during that time. The offense has actually slipped even further, to 27th, yet Boston has kept winning with its most dominant defensive stretch in years.
Ainge didn't break up his team at the deadline, but he also didn't add any significant pieces whose presence would explain the turnaround. Instead, coach Doc Rivers has done a masterful job of getting the most out of the tools he has to work with.
CELTICS PLAYING TIME DISTRIBUTION
Player PRE POST DIFF
Rondo,Rajon 53% 76% 23%
Bass,Brandon 47% 69% 22%
Stiemsma,Greg 14% 34% 20%
Bradley,Avery 34% 44% 10%
Dooling,Keyon 16% 24% 8%
Garnett,Kevin 58% 66% 8%
Pierce,Paul 65% 71% 6%
Hollins,Ryan 0% 4% 4%
Pavlovic,Sasha 12% 15% 2%
Johnson,JaJuan 12% 5% -7%
Allen,Ray 62% 50% -11%
Pietrus,Mickael 34% 23% -12%
Wilcox,Chris 23% 11% -12%
Moore,E'Twaun 14% 2% -12%
Daniels,Marquis 19% 7% -12%
O'Neal,Jermaine 37% 0% -37%
Note: Percentage of available
minutes played is listed, pre and
post All-Star break
Playing time and availability have gone up for Rondo and Garnett, while Allen's court time has taken a hit because of some injury issues. Pierce has stayed on the court more as well as he's gotten into better condition. However, some of the other changes can't be explained by the physical status of Rivers' core. Through necessity and choice, he's given more minutes to Brandon Bass, Avery Bradley and Greg Stiemsma, all of whom have contributed to the Celtics' terrific defensive performance.
Bass moved into the starting lineup when Rivers made his key decision of the season by moving Garnett to center on a full-time basis. The move has paid huge dividends.
For Garnett, the change puts him in a favorable offensive matchup almost every night. He's improved his scoring average from 14.4 points before the break to 17.0 since, while also improving his rebounding, passing and shooting percentage. According to 82games.com, Garnett has a 17.3 PER as a power forward this season, but that has increased to an elite-level mark of 23.1 as a center. Meanwhile, the 15.0 PER he's allowed to opposing centers isn't as good as his mark at the four, but it's still better than the league average for the center position.
Garnett's position switch has garnered all the headlines, but there have been a number of other factors lifting Celtics to the top of the defensive standings.
Bass has been a revelation on the defensive end, contrary to his prior reputation. In past editions of Pro Basketball Prospectus, we've noted that his lack of typical power forward height (he's listed at 6'8") and leaping ability render him a poor rebounder and below average overall defender. According to a number of metrics, Bass has emerged as one of the top frontcourt defenders in the league. MySynergySports.com, which uses video to evaluate a player's efficiency per possession on various play types, has Bass ranked as the ninth-best overall defender in the league. He's sixth on isolations, fifth against post-ups and the best overall at defending players diving to the hoop off the pick-and-roll.
The Celtics have been 1.4 points per 100 possessions better on defense with Bass on the court, and have even rebounded the ball better. You're not going to find a better combination of defensive metrics for a player this season. Whether it's simply Bass becoming more committed, more skilled or the Celtics learning to paper over his deficiencies, Bass has been a key part of Boston's defensive improvement, helping them get around the fact that they don't have a natural starting center.
When the Celtics need an intimidator in the lane, they turn to Stiemsma, a 26-year-old rookie who was plying his trade in the D-League before signing with Boston after the lockout. Stiemsma hasn't played enough minutes to qualify for the leaderboards in rate stats but if he did, he would rank second in the league to Serge Ibaka in block percentage. The Celtics don't rebound as well when Stiemsma plays, but opponents' true shooting percentage drops by 3.5 percent.
On the perimeter, Bradley has become one of the league's standout defensive performers, with an uncanny ability to keep opposing guards in front of him while still managing to pressure the ball. Even though his offensive skillset is that of a low-efficiency two guard, his dogged defensive effort allows him to take on much bigger opponents. He's been so good that Rivers has started bringing Allen off the bench, a thought that would have seemed outlandish at the outset of the season.
We love to quote on-court/off-court numbers, which are important even when the differences seem marginal. There is nothing marginal in the Celtics' defensive uptick when Bradley in the game. For the season, Boston is an astounding 7.7 points per 100 possessions better with Bradley in the lineup. Celtics opponents turn the ball over more and shoot worse when Bradley plays and are shooting just 28.8 percent from 3-point range against Bradley-led lineups.
Rivers has recognized the lack of offensive upside in his roster and gone all-out with defense. The results have been sparkling. The question remains if this unbalanced approach will hold up in the playoffs. Just last Thursday, the Celtics allowed 55 points in the second half at Chicago, losing a game they once led by 13 points to a Bulls team that was still playing without Derrick Rose. The Celtics lost a home game to San Antonio the night before. In both of those defeats, Boston scored 86 points, so you have to wonder if Rivers' squad can keep the scoreboard turning often enough against elite competition. That will be something to watch when Boston takes on Miami on Tuesday night.
A version of this article originally appeared at ESPN Insider .
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