James Harden and the Rockets are having trouble to start the season. (Mike Ehrmann/Getty Images)

The season has barely aged a week and the Houston Rockets are already in trouble.

After losing three regular season games by 20-plus points all of last season, the Rockets opened this year’s campaign with three consecutive 20-point losses, putting the team in rather infamous territory.

If this is alarming, it’s only because it should be: Most preseason predictions projected the Rockets to finish no lower than third in the West. Why? Because Houston returned all of its key cogs from last season’s unit and added Ty Lawson — a quick-twitch player who hasn’t finished lower than 15th among point guards in Player Efficiency Rating the past five seasons. In fact, Houston is one of 14 teams that entered this season with players returning at least 70 percent of last year’s regular season minutes, per Basketball Reference’s roster continuity metric. That should favor their chances for a fast start, not hinder them.

But Houston’s problems can be traced to one surprising — and usually favorable — factor: the analytically advantageous three-point jump shot.

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Last season, the Rockets broke the all-time single-season records in three-pointers made (11.4) and attempted (32.7) per game, while finishing in the top 15 in efficiency on those shots (34.8 percent).

This season, though, Houston has seen a nearly 30-percent downtick in efficiency (24.5 percent, third-worst in the NBA), and ranks in the bottom 10 in three-pointers made per game (7.7). The volume of attempts is hardly the issue: The Rockets are attempting just 1.4 fewer threes per game compared to last season’s average — and rank second in attempted threes per game.

There’s a limited sample size, but why aren’t the shots falling? In short: poor facilitation and a preponderance of attempts coming above the break (also known as the top of the key).

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The Rockets have connected on 13 of 65 above-the-break three-pointers, with 14.3 percent of those shots made on unassisted plays. This is more or less always the least efficient spot for a three-pointer, with corner percentages often much higher. However, the Rockets still managed to net 32.9 percent of those attempts last season, with 22.9 percent coming unassisted. In total, there has been an increase in the team’s proportion of attempts taken above the break this season compared to 2014-15, with a noteworthy dip in efficiency.

Assisted field goal attempts, like catch-and-shoot attempts, are nearly always the superior option offensively but Houston has had difficulty even generating looks for its players: The Rockets rank in the bottom 10 in potential assists, secondary assists, assist points created, assist-to-pass percentage, and, of course, the basic box score assist metric. The numbers are so dismal that it can be easy to forget this team ranked in the top 11 in all of those metrics a season ago. Unsurprisingly, the Rockets have the fourth-highest frequency of isolation plays this season, opting to have Harden sop up possessions trying to cultivate an offensive ecosystem on his own.

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The Rockets are also looking to hoist from beyond the arc early in the shot clock, as they did last season. This year, the team is tied with the Golden State Warriors for first in three-point attempts taken with 22-18 seconds remaining on the shot clock. However, although the teams are tied in volume of attempts within that range, the Warriors are connecting on nearly 35 percent more of their attempts than Houston is (56.5 percent compared to 21.7 percent). Few teams in the NBA are more trigger-friendly early in the shot clock from deep than Houston and Golden State, but, as shown below, the Warriors are significantly more efficient within that range.

Again, in terms of roster makeup, Houston wasn’t brimming with elite three-point shooters last season — among players who played in at least 50 regular season games for Houston, only Jason Terry, James Harden, Trevor Ariza, Patrick Beverley and Josh Smith shot better than 33 percent from deep, and none shot better than 38 percent — but this year’s roster is a barren wasteland through three games. Harden, last season’s MVP runner-up, is shooting a horrid 9.4 percent from distance; Beverley has connected on three of his 11 attempts; and Ariza is shooting significantly lower than his career average.

McHale has watched his unit net fewer than 28 percent of its three-point attempts just 19 times since the start of last season; three have come in the past week. The Rockets still have 79 regular season games remaining, easily enough time to propel themselves back into the contending tier of Western Conference teams … or plummet to the bottom of the merciless Southwest Division.