The Nets have now played ten games since the unfortunate injury to Yi Jianlian. To be more specific, they’ve actually played eleven, since they snuck in the victory over Philadelphia the other day in the second half of a back-to-back before I could cobble this report together. I thought that ten games would be a threshold for taking a close look at how the loss of Yi has affected the team’s performance. What I plan to do in this piece is to simply compare various metrics for the ten games immediately prior to Yi’s injury to the games since he suffered his injury, and to try to make some conclusions regarding the effect that his loss has had. Just to be complete, I’ll extend the post-injury data to include the Philadelphia game. Thus: ten games before, eleven after. For the purposes of this analysis, I’ll completely ignore the game that Yi injured his finger (he missed about half the game, if I remember correctly).
If you remember, during the two games immediately prior to Yi’s injury, he had started to really come into his own, averaging 21 points and 9.5 rebounds while hitting over 50% of his shots (he was enjoying a similarly good game on January 9 when he was injured). For the entire ten game period, however, his performance was fairly erratic, even including those last few games. All in all, though, his overall stats were better than Ryan Anderson’s have been in the games since. Ryan replaced Yi in the starting lineup, so to a certain extent we’ll be looking at his contributions.
Before we begin, let me add that there may be other events that could have affected team performance during the past 21 games. Devin Harris missed two games immediately preceding Yi’s injury and most of a third. Bobby Simmons missed a pair of games in late December as well. Also, by all accounts, Harris and Vince Carter have been suffering from nagging injuries themselves over the past few weeks, which have undoubtedly had an effect on team performance. But you can never reproduce laboratory conditions in real life, so we’ll have to do what we can.
TEAM RESULTS—PRIOR TO INJURY
In the ten games immediately prior to Yi’s injury, the Nets earned a record of 5-5. However, they did get outscored during this period by an average score of 97.3-94.9, so perhaps they were a little bit lucky. The Nets did go 2-0 during this stretch in games decided by less than five points, which seems to back this up. In fact, we calculate that during this period the Nets have scored 102.4 points per 100 possessions during this stretch, while giving up 105.4, so we probably would have expected them to have a record around 4-6.
TEAM RESULTS—SUBSEQUENT TO INJURY
In the eleven games immediately following Yi’s injury, the Nets earned a record of just 3-8. Just like the prior ten games, they did get outscored during this period, but the gap worsened a bit: Now the average score was 100.0-92.6. Their record during this stretch is probably a pretty accurate reflection of their point differential. The Nets did go 2-2 during this stretch in games decided by less than five points, which is more in line with what we’d expect. Although the Nets scored fewer points per game, their points per 100 possession computes to 101.6, nearly identical to what it was prior to Yi’s injury. The lower point total, therefore, was a result of a slower pace of play—not at all surprising given that they played Boston twice and San Antonio once during this stretch of games. On the defensive end, though, we see a dramatic reduction in effectiveness, as the Nets have given up 109.9 points per 100 possessions, which is horrible, to put it lightly.
TEAM RESULTS—NET
Summary: Since Yi’s injury, the Nets have scored 2.3 fewer points per game and surrendered 2.7 MORE points per game—a five point swing. As mentioned above, however, they have scored roughly the same number of points per 100 possessions, but their defense has been dramatically worse—four and a half points per 100 possessions. Of course, the quality of the opposition could have something to do with this. We don’t know whether Yi’s injury is directly responsible for this—undoubtedly, the injuries suffered by Devin and Vince have played a part—but it is certainly worth noting. Just for the record, in both time periods the Nets committed fewer turnovers than their opponents. In fact, their margin has increased; in the ten games prior to Yi’s injury, the Nets committed seven fewer turnovers than their opponents; since the injury, they have committed twenty-two fewer.
PERFORMANCE OF VINCE AND DEVIN—PRIOR TO INJURY
Next I thought I’d take a look at how Vince and Devin have performed during the two periods. Is the recent poor record a reflection of their shooting? Let’s take a look. In the ten games immediately prior to Yi’s injury, Vince shot a mere 40.5% from the floor on 17.8 attempts. Similarly, Devin shot just 41.0% from the floor on an average of 14.6 attempts (remember that Devin played just eight of the ten games). If we eliminate the game on January 5, when Devin took three shots and left for good, we calculate that he averaged 16.3 shots per game. Regardless, one thing is clear: Devin and Vince were not carrying the Nets to their 5-5 record during this stretch of games. They had already begun to underperform.
PERFORMANCE OF VINCE AND DEVIN—SUBSEQUENT TO INJURY
In the eleven games immediately following Yi’s injury, it has been more of the same from Vince and Devin. Vince has shot a horrific 38.4% from the floor on 14.6 attempts per game, while Devin has shot 38.6% on an average of 14.5 attempts.
PERFORMANCE OF VINCE AND DEVIN—NET
Summary: As bad as Vince and Devin had been in the ten games prior to Yi’s injury, they have been even worse since. They have also taken fewer shots. Part of that, however, is due to their joint benching during the second half of the second game against the Celtics. If we eliminate that game from the number of attempts, they will increase to 15.3 (Vince) and 15.4 (Devin). Part of it may also be due to a slower pace of play in those games due to the style of the opposition. They may also have drawn more shooting fouls; I have not examined that. Regardless, there is no question that Vince and Devin have failed to step up and have been at least partially (if not mostly) responsible for the team’s record over the past eleven games, and probably the primary reason that the team’s scoring has decreased. Perhaps, however, that one reason for their poor shooting has been that without Yi, the Nets have lacked a consistent three-point thread, allowing the opposition defenses to converge on the guards. Let’s take a look at that next.
THREE-POINT SHOOTING—PRIOR TO INJURY
In the ten games immediately prior to Yi’s injury, the team took an average of 19.0 three-point shot attempts, making 7.2, for a shooting percentage of 37.9%. To put it another way, the Nets scored an average of 21.6 points per game on three-point shots.
THREE-POINT SHOOTING—SUBSEQUENT TO INJURY
In the eleven games immediately following Yi’s injury, the team took an average of 20.2 three-point shot attempts, making 7.4, for a shooting percentage of 36.6%. To put it another way, the Nets scored an average of 22.2 points per game on three-point shots.
THREE-POINT SHOOTING—NET
Summary: Not much difference, to be honest. The Nets took 1.2 more three-point shots after Yi’s injury, making 0.2 of them. Had they shot from behind the arc at the same rate, they would have made an average of .455 more three-pointers per game instead .2—so this lower shooting percentage has cost them roughly three-quarters of a point per game. The conclusion is that the Nets have overcome the loss of Yi pretty well with respect to their long-range shooting. Incidentally, over the course of the season, the Nets have shot 37.6% from behind the arc. Only five teams have shot better than 38.0%.
REBOUNDING—PRIOR TO INJURY
By all accounts, Yi has rebounded the ball better than anyone expected. Has the team rebounding rate suffered in his absence? Let’s look at the numbers. During the ten games prior to Yi’s injury, the Nets averaged 10.5 offensive rebounds per game, while the opposition grabbed 31.5 defensive rebounds. We can define the "offensive rebound success rate" as (OR)/(OR+OppDR). By this metric, the Nets were able to secure 25% of the potential offensive rebounds. We can do the same calculation with regard to defensive rebounds. The Nets secured 31.2 defensive rebounds per game, while the opposition grabbed 8.8 offensive rebounds, giving the Nets a success rate of 78%.
REBOUNDING—SUBSEQUENT TO INJURY
During the eleven games since Yi’s injury, the Nets averaged 11.0 offensive rebounds per game, while the opposition grabbed 33.1 defensive rebounds. Thus, the Nets were able to secure 24.9% of the potential offensive rebounds. On the defensive end, the Nets secured 27.7 defensive rebounds per game, while the opposition grabbed 10.0 offensive rebounds, giving the Nets a success rate of 73.5%.
REBOUNDING—NET
Summary: We can see that while the Nets’ offensive rebounding has remained about the same, their defensive rebounding has taken a dive. The difference between a 78% success rate and a 73.5% success rate is about 1.7 rebounds per game at this level of opportunities—that is, the Nets are allowing the opposition 1.7 more offensive rebounds per game than we would have expected had Yi not gotten injured. That is a huge number, and represents possibly as many as two points per game.
YI VERSUS RYAN ANDERSON: PLUS-MINUS
During the ten games prior to Yi’s injury, the Nets were outscored by a total of 24 points. Yi was a plus-13 during this period, meaning that he outperformed the team by plus-37, if that makes sense. After Yi went down, he was replaced by Ryan Anderson in the starting lineup. During the next eleven games, the Nets were outscored by a total of 81 points. Ryan Anderson’s personal plus-minus during this period was a minus-41.
I’ve also taken a look at how the starting five-man unit performed during these games. I’ve discovered that, in the ten games prior to Yi’s injury, the starters were a combined plus-five. Note that in two cases the starting five included Keyon Dooling in place of Devin Harris, and on two occasions Trent Hassell instead of Bobby Simmons. In the eleven games since Yi’s injury, however, the starting five (with Ryan replacing Yi) earned a total of . . . plus-four! In other words, during this eleven game stretch, the starting five has outscored the opposition when they have been on the floor, most often against the opposition’s starting five.
That suggests, also, that in the time that Ryan has played without the other starting four, the team has been absolutely horrible. He is a minus-45 in roughly 97 minutes of play during such situations, by my count. How much of that is Ryan’s fault is unclear, but we could probably say with some certainty that he isn’t helping things when he is on the court with some of the reserves right now.
The conclusion here seems to be that replacing Yi with Ryan Anderson in the starting lineup has not resulted in a loss of productivity among the starting unit. However, when some number of reserves is in the game—including when Ryan is matched with some reserves—the team production has fallen apart. Previously, when Yi was paired with reserves, the team performed much better.
CONCLUSION
It appears as though the loss of Yi has had three primary negative effects. First, the team’s defensive efficiency has eroded significantly. Second, the defensive rebounding efficiency has suffered. Third, the bench has performed poorly, especially when Ryan has been paired with some of the reserves. This is an odd conclusion, because Ryan seemed to perform fairly well with the reserves before he was elevated into the starting lineup. Perhaps he is playing too many minutes, and his effectiveness has suffered as the game has dragged on, I really don't know.
Again, as stated initially, there could be other factors for some of these results. Injuries, the quality of the opposition, poor play from other players. However, it would seem to be a bit of a coincidence that this change occurred dramatically right around the time that Yi was injured.
Regardless, I think we can all agree on one thing: Hurry back soon, Yi!