The Houston Rockets and the defensive decline of Trevor Ariza

The Houston Rockets have a defensive problem.

That is the key reason why the team has fallen from reaching the Western Conference Finals last year to a sub-.500 team. The team has gone from 8th in defensive rating in the 2014-15 season to 26th this season.

And as the Rockets have collapsed on the defensive end, James Harden is once again getting attacked for his lack of defense. This is deserved. Harden has visibly gotten worse throughout this year. Look at how Joe Johnson, who is averaging 11 points per game this season, scored 16 and 22 points in his two games against the Rockets.

Or James Harden missing out on defense against the Dallas Mavericks.

But Harden’s defense is not solely responsible for such a dramatic fall. And as Rockets fans and sportswriters point fingers, one player who has escaped opprobrium is Trevor Ariza.

The Rockets signed Ariza in 2014 to be the defensive swingman complement to Harden. But Ariza is now 30 years old and has been in the league since 2004. It would hardly be surprising to see him begin to decline, and he has.

The focus at the team’s Monday victory over the Utah Jazz was on how Montrezl Harrell was not called for fouling Jeff Withey on his dunk attempt.

But before that, Trey Burke caught Ariza completely off guard and drives past him.

While the Jazz failed to score, the defensive failure by Ariza gave Utah a golden opportunity to tie the game.

Or look at the December 31 game against Golden State, where the Rockets humiliatingly lost to a shorthanded Warriors team playing on the second night of a back to back. The big story of the game was that after struggling against the Dallas Mavericks, Klay Thompson dropped 38 points on the Rockets. Everyone lined up to castigate Harden for his defense against Thompson.

But Ariza is supposed to be the perimeter defender on the Rockets, and the one chasing Thompson around and preventing him from scoring 38. If he is not doing that, then what good is he?

And this analysis is further supported by the numbers. Ariza averaged 8 defensive win shares (DWS) in his 2013-14, and 6.6 last year. But as of right now, he is on rate to only have a little more than 2 at the end of the season.

Houston’s defensive weaknesses are because their perimeter players cannot stop anyone. But the fact is that all three Houston perimeter players – Ariza, Harden, and Patrick Beverley – are to blame for how the Rockets have fallen apart defensively. While Harden is viewed as the superstar, Houston’s defense should be fine if the other two, who are known as defense-first players, actually play defense.

If Houston is going to turn things around and play defense at the level they did last year, then everyone is going to have to step up and communicate better. And that should start with the player who the Rockets signed to play defense in the first place.