The defensive numbers the Bulls have been putting up this season, especially at home, are hard to wrap your mind around.
Think of it like this: there are five NCAA Division I men's basketball programs in Chicago. Three of those teams play slow-down basketball, especially Loyola-Chicago, one of the most deliberate teams in the country. Collectively, those five teams have allowed 65.7 points in 40 home games this season. Meanwhile, the Bulls -- who we point out play in the National freaking Basketball Association -- have allowed 66.8 points in five games at the United Center. Four of Chicago's five home opponents have scored under 70 points this season. Last season there were just five instances all year in which a team scored under 70 -- in the entire league.
Even after Chicago endured one of those heavy-footed losses on Monday, the type that are going to be so prevalent in this NBA season of nightmarish scheduling, it still leads the league by allowing just 85.0 points per game. Last season, the Bulls' defense ranked second to Boston when it allowed 91.3 points per contest. Is the Bulls' defense really 6.3 points per game better than last season? At this rate, Chicago would allow the sixth-fewest points per game of the shot clock era (1954-55 to present).
By now, those who relish properly contextualized statistics are probably pounding on their keyboards because they think this analysis is headed in the wrong direction. Hang with us. The numbers you've seen so far have been selected because they have been floating around the Web the last couple of days and rolling off the tongues of NBA broadcasters from coast to coast. They aren't exactly misleading. After all, a team almost certainly can't hold opponents to 66.8 points in any subset of its schedule and not be an outstanding defensive team. The Bulls are a great defensive team, possibly the best in the league. However, once you put these numbers in their proper perspective, you find some nuances in them and, as always, the most interesting lessons are in those nuances.
The first thing that students of tempo-free analysis already know is that on a per-possession basis, the Bulls haven't even been the best defensive team in the league. The Sixers have allowed just 89.7 points per 100 possessions this season; Chicago is second at 92.7. The Sixers play about 3 1/2 possessions per game faster than the Bulls, which is why their raw defensive points per game figure isn't quite as sterling. So the Sixers are the league's best defensive team so far, right?
As you've probably guessed, that answer isn't quite so simple, either. You have to account for the quality of offenses each team has played so far this season. With so few games in the books, there is a wide disparity in schedule strength from team to team. When you factor the opponents Chicago and Philadelphia has played, you find that the Bulls actually come out ahead.
----- SIXERS DEFENSE BY OPPONENT -------- ----- BULLS DEFENSE BY OPPONENT ----------
Date Opponent OEFF xPA PA NET Date Opponent OEFF xPA PA NET
12/26 Portland 102.0 98.1 107 8.9 12/25 LA Lakers 100.7 93.2 87 -6.2
12/28 Phoenix 101.4 95.8 83 -12.8 12/26 Golden St. 100.0 92.8 99 6.2
12/30 Utah 100.3 95.1 102 6.9 12/29 Sacramento 93.8 88.2 98 9.8
12/31 Golden St. 100.0 95.0 79 -16.0 12/30 LA Clippers 105.1 97.0 101 4.0
01/04 New Orleans 96.5 90.1 93 2.9 01/01 Memphis 97.0 90.6 64 -26.6
01/06 Detroit 93.7 87.0 73 -14.0 01/03 Atlanta 103.3 95.1 74 -21.1
01/07 Toronto 95.0 88.9 62 -26.9 01/04 Detroit 93.7 85.0 83 -2.0
01/09 Indiana 98.4 93.3 86 -7.3 01/06 Orlando 106.8 97.9 83 -14.9
01/10 Sacramento 93.8 90.2 85 -5.2 01/07 Atlanta 103.3 95.1 109 13.9
01/11 New York 97.4 93.6 85 -8.6 01/09 Detroit 93.7 85.0 68 -17.0
01/13 Washington 88.3 84.4 89 4.6 01/10 Minnesota 98.3 92.0 100 8.0
01/14 Washington 88.3 84.4 90 5.6 01/11 Washington 88.3 82.5 64 -18.5
01/16 Milwaukee 97.7 93.2 82 -11.2 01/13 Boston 100.0 91.2 79 -12.2
01/14 Toronto 95.0 86.8 64 -22.8
01/16 Memphis 97.0 90.6 102 11.4
13 TOTALS 96.4 1189 1116 -73.0 15 TOTALS 98.4 1363 1275 -88.0
AVG>> -5.6 AVG>> -5.9
(KEY: OEFF -- opponents' offensive efficiency; xPA -- expected points allowed based on
opponent efficiency and expected game pace; PA -- actual points allowed; NET -- points
allowed above or below expected)
If it's important for you to declare the Bulls as the league's best defensive team, you wouldn't be wrong. As for our other question -- whether or not the Bulls are better defensively than last season -- you have to account for the league-wide drop in offensive efficiency. The average team last year scored 104.5 points per 100 possessions, this year that number has plummeted to 99.97. (We include the extra decimal on the latter to illustrate that the average has fallen below a point per possession.) Overall, the average team is scoring five fewer points per game than last season. Thank you, lockout.
The Bulls led the league last year by posting a defensive efficiency of 97.4 points per 100 possessions, which was 6.8 percent better than the league average. Chicago's 91.7 defensive efficiency figure this year is 8.3 percent better than the league, so on that basis you can say that the Bulls are even better on the defensive end. Because of Chicago's defensive dominance on its home floor, that statement feels more solid when you consider that the Bulls have played 10 of their 15 games on the road.
Chicago's defensive success starts with coach Tom Thibodeau, who views defensive prowess as the key to everything from winning basketball games to the recovery of the national economy. No matter what happens in a game, Thibodeau grouses about his team's defense. If they are losing a game 17-15 after one quarter, it's because they aren't playing good enough defense. If shots aren't falling on the offensive end, it's because the defense isn't creating enough pressure to open the floor and create good shots. The one offensive category that Thibodeau will complain about is turnovers, and that's only because miscues in the open floor lead to easy baskets on the other end. The mantra filters down to the Bulls' roster. Anytime you ask Derrick Rose what the team needs to do to get back in a game or what happened to spark a comeback, he always cites defense. It's that way all through the locker room.
Thibodeau's scheme is basically the same as it was when he designed the defenses as an assistant in Houston and Boston. It starts with consistent on-ball pressure to delay a team from getting into its offensive sets. To that end, Rose has improved by leaps and bounds from where he was under former Bulls coach Vinny Del Negro. If you have the means, go back and watch the video from Chicago's game against the Clippers on Dec. 30. Rose made life miserable for Chris Paul. This season, the focus for Rose on the defensive end has been to improve as a help defender. Rose has been excellent on the ball under Thibodeau, but that has sometimes come at the cost of not rotating to open shooters. Now Rose over-helps at times, by design, trusting that his coach's proven schemes will take up the slack. They usually do.
Thibodeau emphasizes overloading the strong side of the opponent's offense, making entry into the lane near impossible. It is rare to see an opponent drive from the perimeter to the basket without someone stepping in to help -- the Bulls allow the league's third-lowest percentage at the rim (57 percent), according to HoopData.com. When the Bulls struggle on defense, it's usually because a weakside three-point shooter has gotten hot and someone has gotten sloppy in scrambling back to close on open shooters. It doesn't happen often, and not for very long. While the Bulls have allowed the league's seventh-worst three-point percentage, no team has allowed fewer attempts from behind the arc.
When you've got the lane closed off and are successfully pinching the three-point line, all that's left are long two-point jumpers, the most inefficient shot in basketball. Not surprisingly, the Bulls force the third-most long-twos per game in the league. It's the perfect statistical mixture for outstanding team defense.
All this said, the Bulls' depth is really what boosts the team's defense from good to great. The combined defensive ability of second unit big men Omer Asik and Taj Gibson has gradually gotten more attention from those who cover the league, as well as opposing coaches. The meme among visiting coaches at the United Center this season is that both Asik and Gibson would start for many NBA teams, which is certainly the case and for good reason. It's not unusual for Thibodeau to leave Asik, Gibson or both on the floor in the fourth quarter of close games at the expense of better-known teammates Joakim Noah and Carlos Boozer.
Let's state this more emphatically to drive the point home: The Bulls' second unit is the best defensive lineup in the NBA. According to BasketballValue.com, the group (which typically includes starter Luol Deng) is allowing about 61 points per 100 possessions in a small sample of 49 minutes--easily the best of any qualifying lineup in the league. This is despite the fact that undersized John Lucas III has been the primary backup for Rose instead of the injured C.J. Watson, the Bulls' best defensive point guard. Last season, among units with at least 100 minutes together, the top two groups featured Asik, Gibson, Deng and Ronnie Brewer. The two groupings fared about equally well with either Rose or Watson at the point.
Noah was the only Bull honored as an All-Defensive performer by the league last season, making the second team, but in fact he lags behind Asik, Gibson and Deng on his own team. Thibodeau lauds Deng so consistently that you would think it was he, not Rose, that won the MVP award last season. Deng has reached the point where he's so consistently called underrated that he probably no longer is. He's one of the five best small forwards in the league and only LeBron James is better on the defensive end. The honors should finally start pouring in for Deng this season, both in terms of an All-Star berth and all-defense recognition.
The Bulls' defensive success is a blend of Thibodeau's philosophy, consistency of message and the depth of his personnel in the frontcourt. So far, it's been a lethal mixture resulting in some of the most amazing defensive numbers we've seen in awhile. Chicago can't match the firepower of James, Dwyane Wade and Chris Bosh in Miami, but if it keeps playing defense like this, it may not need to.
A version of this article originally appeared at ESPN Insider .
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