The Trail Blazers are slumping, and the biggest reason is the team has stopped defending.

Portland has lost seven of its past 10 games. During that stretch, the Trail Blazers have the worst defense in the NBA, allowing 118.2 points per 100 possessions. To put into perspective just how bad that number is, consider that the worst defensive team in the NBA last season, the Phoenix Suns, allowed 111.6 points per 100 possessions. The Blazers, over the past 10 games, are 6.6 points worse than last season's worst defensive team.

There's no sugar-coating this. The Trail Blazers' defense is atrocious and there's no excuse for it. The blame falls on coaches, players and the front office. If Portland can't fix its defensive woes, this team will have a hard time competing in the Western Conference this season.

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On ESPN's real plus-minus rankings, this author's favorite comprehensive individual analytic, you have to scroll all the way to the last page to find the Blazers' two most prominent players. After last season, when Damian Lillard and CJ McCollum showed vast improvement on defense, it's disheartening to see them rank as two of the worst defensive players in the NBA again. McCollum ranks 421st out of 442 players. Lillard ranks 419th.

Here are the Blazers' rankings in defensive real plus-minus this season:

22. Jusuf Nurkic +2.21

47. Al-Farouq Aminu +1.59

98. Caleb Swanigan +0.99

118. Jake Layman +0.81

131. Zach Collins +0.69

139. Meyers Leonard +0.62

173. Maurice Harkless +0.38

179. Evan Turner +0.34

249. Gary Trent Jr. -0.21

315. Seth Curry -0.74

361. Anfernee Simons -1.03

377. Wade Baldwin -1.17

419. Damian Lillard -2.08

421. CJ McCollum -2.15

432. Nik Stauskas -2.63

It's easy to spot a trend. Portland has some good defensive players. Nurkic ranks among the league's best defenders and Aminu's spot in the Top 50 shows he's doing his job as well. Other defenders such as Zach Collins, Maurice Harkless and Evan Turner have been passable for Portland, at least.

But the Blazers don't have a single guard playing effective defense right now, which is sabotaging the team's ability to compete on the defensive end of the court. Every guard on the roster has a negative rating in defensive real-plus minus, and Lillard, McCollum and Stauskas are three of the worst defenders in the entire league this season.

Portland won't get better until the front court starts carrying its weight on defense.

The latest batch of NBA power rankings wasn't kind to the Blazers this week. Take a look:

The Athletic: Blazers rank No. 10 (down 1)

What they wrote: The Portland Trail Blazers are a little lucky to still be in the top 10. This is the lowest they’ve ranked this entire season, and their season is teetering a bit. Portland has won just once in their last six games, and that one win happened against the Orlando Magic. They barely pulled out a home victory in that win. Milwaukee and Golden State blew them out. The Clippers and Nuggets beat them in close games. Then San Antonio handled them pretty well on Sunday to keep Portland down. This Portland team looked like they could position themselves with their continuity and dynamic backcourt to be a top team in the West.

Now they’re only 1.5 games ahead of New Orleans, Houston, and Sacramento — who are all currently out of the top 8 in the West. Over these last six games, the Blazers have the worst defense in the NBA. Part of this is greatly skewed by the games against Milwaukee and Golden State. However, even in their victory over Orlando, they defended horribly. The Blazers can’t defend the 3-point line right now and that trickles to them not being able to protect the basket. Their schedule from now through the first week of January is going to be brutal for them. Damian Lillard and CJ McCollum can’t carry them every night if nobody gets stops on this team.

Portland is in danger here.

CBS Sports: Blazers rank No. 10 (down 4)

What they wrote: The Blazers started the season as hot as anyone, but have lost five of six, albeit against a tough schedule. Simply put, they need another dude to get buckets. CJ McCollum and Damian Lillard have been awesome; Jusuf [Nurkic] is the only other guy on the team averaging more than nine points per game. But the defense has been the bigger issue. During that six-game stretch, the Blazers have the lowest-rated defense in the NBA.

ESPN: Blazers rank No. 12 (down 3)

What they wrote: The Blazers have lost five of the past six games and two straight -- so what's the problem? Portland has been horrible defensively, allowing 123.2 points per game in those five losses. The Blazers have also lost seven of their past 10 games after jumping out to a 10-3 start.

Sports Illustrated: Blazers rank No. 12 (down 3)

What they wrote: After Dame Lillard exploded against the Magic to get Portland a win, the squad let one get away against the Nuggets. With the West so tight from top to bottom, the Trail Blazers saw themselves slide down the standings by losing five of their last six. Losing four of those games to teams in the West will also feel like a killer when it’s time for tiebreakers to determine playoff seeding.

NBA.com: Blazers rank No. 13 (down 6)

What they wrote: The Blazers haven't lost to a bad team since October, and they are an open C.J. McCollum jumper from beating the streaking Nuggets on Friday. But they're 3-7 over the last three weeks, allowing a league-worst 118.2 points per 100 possessions in that stretch (which has taken them from second to seventh in the West). The Denver loss was one of only two in the 3-7 stretch that was within five points in the last five minutes and they needed 41 points from Damian Lillard to edge the Magic (who were without Aaron Gordon) on Wednesday. Their new (old?) starting lineup (with Maurice Harkless back at small forward) is a plus-15 over the last four games, but bench minutes have been a problem. In fact, Zach Collins has registered a negative plus-minus in 10 of his last 11 games.

Jared Cowley writes about the Trail Blazers and other topics for KGW.com. He's also the co-host of the 3-on-3 Blazers podcast (listen here). You can reach him on Twitter @jaredcowley.