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Celtics by the numbers

05.23.10 at 12:09 pm ET

As we all know by now, the Celtics have become a different team than the one they were in the regular season and the numbers bare that out.

Fair warning: This post uses non-traditional metrics to look for statistical trends. They are taken straight from the Celtics page on and are by no means the end all and be all of analysis. As the guru of advanced basketball stats Dean Oliver once told me, numbers are useless if they don’t help tell a story, so we’ll use these to help paint a picture of how the Celtics have turned things around.

The important thing to remember is that these stats are adjusted for pace (possessions used during a game), which simply allows us to compare the numbers found in the box score to other players on other teams, regardless of how fast or slow they play. If you’re interested in understanding more, B-R has a very useful glossary page.

As you might expect, some interesting trends have developed with the Celtics over the course of 14 playoff games:

PER (Crunches box-score numbers into one overall number. 15 is considered average):

Not surprisingly, Rajon Rondo is the overall leader at 19.8. That’s a good number, but it’s not a traditional superstar level. Kevin Garnett is second at 18.2, which notes his increased scoring and rebounding. Interestingly the Celtics have four players over 14: Tony Allen, Glen Davis, Ray Allen and Paul Pierce. That shows the Celtics balance more than any failing on their part.

True Shooting Percentage (Counts 2’s, 3’s and free throws into one number)

Ray Allen is the leader here at almost 60 percent. The next three: Tony Allen, Rasheed Wallace and Glen Davis. Think the bench has had better production? You’re right. They are shooting a much higher percentage, which might have something to do with the fact they are getting more playing time with Rajon Rondo who has averaged 42 minutes a game.

The biggest gainer? Sheed, who went from barely over 50 percent to over 58 percent. He’s made almost 50 percent of his 3-point attempts (11-for-24), which is also a nod to his better shot selection.

Offensive Rebounding Percentage (The percentage of offensive boards a player gets per 100 possessions, adjusted for pace)

The Celtics were not a very good offensive rebounding team during the regular season. There’s a good reason for that: Doc Rivers doesn’t put a high priority on getting them. Their strategy is to get back on defense and he discourages crashing the glass without a clear advantage.

The Magic have provided an opening however because of how they play and the Celtics have gathered up 23 offensive boards on the first three games.

“They’€™re a help oriented team just like we are,” Rivers said. “If you can get to the paint and get a shot at the rim, there’€™s usually a guard or a big trying to block your shot so there’€™s usually a big that’€™s free and we want to take advantage of that. If you’€™re man helps off of you, go to the glass. If not, get back.”

But offensive rebounding has not been that big of a factor for the Celtics. Kendrick Perkins and Glen Davis have actually seen their percentage go down and Rajon Rondo’s has been about the same. Kevin Garnett has shown a small uptick, but that’s about it.

They’ve made a much more dramatic gain on the defensive side of things.

Defensive Rebounding Percentage

The Celtics used to be a dominant defensive rebounding team, but this season they slipped all the way down to 12th in terms of percentage. All those offensive rebounds that they allowed and made them look slow? Gone. The Celtics have returned to their defensive rebounding roots.

Who’s responsible for the improvement? The guards. Rondo, Allen and Pierce have all lifted their percentage (as has Glen Davis). Defensive rebounding was the key to the series with the Cavs and while the big men held down the inside, it was the guards who scrambled for long rebounds, loose balls and tips.

Turnover Percentage (Turnovers per 100 possessions)

The Celtics ranked 27th during the regular season in turnovers (14.5 percent) and they have cut down on that number in the postseason (13.7) which is still below league average, but every little bit helps.

Rondo and Tony Allen have reduced their turnovers as has Rasheed Wallace, even though his were not very high to begin with. There have been modest improvements up and down the lineup. (Pierce’s are a little higher, but not dramatically).

Again, it’s on the defensive end where the Celtics have shown an even bigger improvement. They ranked second in forcing opponent turnovers during the regular season (15 percent), but they have become even better during the postseason (16.3 percent) and no one is really close. The Lakers, to cite one example, force turnovers on only 11 percent of their opponents possessions.

Usage Rate (An estimate of the number of possessions used by a player when he is on the floor)

An easy way to think about Usage is a team that distributed its production evenly would have five players posting a 20 percent usage rate. Basketball doesn’t work that way, of course, and a high Usage Rate can indicate an ability to create a shot for yourself, or a desire to create a shot for yourself if you happen to play for the Warriors. It’s an interesting number that requires some context before jumping to conclusion.

The Celtics held very close to the Hickory High ideal during the regular season as four of their five starters had rates over 20 with Pierce using the most at 23.8 percent.

For reference, the highest rate in the league was Dwyane Wade at almost 35 percent. LeBron James was second, which illustrates how the Celtics defense has had to defend dominant individual players. (Kobe Bryant was fourth).

Balance has been the key for the Celtics offensively and that has held true during the postseason where the numbers have stayed consistent. If anything, the Celtics have been more selective. Perkins and Wallace have both seen their rate decrease, while Rondo’s has gone up slightly. (On a side note, Nate Robinson has soaked up 33 percent of the possessions he’s played, which is D-Wade territory.)

Rivers has talked repeatedly of trusting the offense and allowing the opportunities to develop within that structure and his players have continued to buy in to the program.


What’s fascinating about what the Celtics have done is that they haven’t dramatically changed the way they play. They’re simply doing those things better, especially on the defensive end.

Rondo really hasn’t dominated the offense any more than he has in the past. The Celtics still turn it over a little more than they should and they haven’t morphed into a bunch of DeJuan Blair’s on the offensive glass. But they have improved in those areas and that’s certainly a difference in turning a 50-win also ran into a legit championship contender.

The bench has picked up their play dramatically, which is probably a result of a tightened rotation as well as more time on the court with Rondo leading the charge.

But there’s no mystery involved, no deep secret to be revealed about how they’ve been able to do this. They’ve simply gone back to their roots defensively and cut down on some dubious decision-making on the offensive end.

You can say they flipped a switch, or improved their focus and energy and you wouldn’t be wrong. You can also credit improved health, as evidenced by an increase in minutes for Pierce, Allen and Garnett.

Pierce had the most honest statement to date when asked about the difference between the regular season Celtics and the team that is one game away from an improbable return to the NBA finals.

“I know it’€™s starting to look that way,” he said after Game 2 in Orlando in response to a question about flipping the switch. “Even though we lost some games down the stretch there were some things that we were doing that we were seeing that we were turning the corner. We saw it coming, we stayed positive. I know it’€™s starting to look that way, but maybe you can.”

“We’€™re keeping our eye on our goal,” he continued. “It doesn’€™t matter what say about us, what people wrote, what people say on television. We know the team we have is championship-caliber and it’€™s starting to come together at the right time. But the things that were said were probably deserved. We didn’€™t play well. We didn’€™t play consistent. A lot of the flak we got was probably deserved.”

But as Rivers shot back at the press toward the end of the season after a deflating loss to the Wizards:

“If we make a run in the playoffs, will you forget it? If we don’t, then it’s probably who we were all year — an inconsistent team — at least in the second half of the year. We’ll find that out.”

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