When we talk about Yao Ming as a basketball player, we usually begin with a statement about his size. He is listed at 7-foot-6, although Henry Abbott maintains he is closer to 7-3. Regardless, in a game of giants, he stood above every one of his peers.
The Yao discussion usually transitions then from size to skill. With precise footwork and smooth mechanics in the post, he represented a relic from a more fundamentally conscious past. It seems unfair that one could release the ball from such towering heights, but it's downright criminal to pair his genetic gift with the touch of a shooter. In a related note: Yao shot 83.3 percent from the free throw line over his career, whereas an average 7-footer shot under 70 percent. Dirk Nowitzki is the only 7-footer to shoot better over his career.
The combination of offensive skill and gargantuan size propelled the Houston center to eight All-Star selections, a couple of 20-and-10 seasons in the scoring and rebound columns, and a career PER that ranks on par with NBA legends Oscar Robertson, Jerry West and Moses Malone. Playing for Houston GM and statistical wizard Daryl Morey, Yao was a model of efficiency for all nine seasons that he played in the NBA.
But the interesting thing is that when we talk about Yao, no one seems to spend much time discussing his defensive impact. The Rockets have been devastated by Yao's injuries over the years, but the most gaping hole left by Yao can be found on the defensive end of the court.
How can we tell? Let's take a look at how the Rockets have fared with and without Yao on the floor. More specifically, we'll examine how they performed on a per-possession basis by taking a look at their offensive and defensive efficiencies. We have data going back to the 2007-08 season, which gives us roughly 5,000 minutes of Yao on the court and about 10,000 minutes with him off the court.
What do we find?