The Phoenix Suns have one of the worst defenses in the NBA this season and this was evident in their loss to the Boston Celtics on Saturday. Despite a good offensive effort that saw them almost cause an upset before narrowly losing 116-111, it was all undone by a complete lack of effort on the defensive end.It certainly explains their 8-16 record in the Western Conference as they appear to have a complete disregard for playing on both ends. But there was one defensive possession, in particular, against the Celtics that showed just how bad the Suns are in this regard. They displayed why they rank dead last in both opponents’ points per game and defensive rating with one of the most embarrassing sequences you're likely to see all season. In the third quarter of the contest, Celtics guard Marcus Smart launched an uncontested three-pointer, with not one Boston player in the paint for a rebound attempt.Yet somehow Phoenix allowed the basketball to return right back to Smart after he missed and he duly put up another attempt from beyond the arc with still no Suns player closing out to him. Smart also missed this attempt but Al Horford managed to grab the rebound and keep the possession alive despite being outnumbered in the paint.After the big man shuffled out to the corner and realized no Phoenix player even attempted to defend him, he cashed in by sinking a three-point bucket.Here's a clip of the ugly sequence by the Suns:

As you'd expect, they were ripped across social media with fans enjoying making fun of their meek attempts. 

The effort of veteran Tyson Chandler, in particular, was truly awful for a player of his experience who is regarded as one of the leaders of the team. 

Maybe the craziest part of this disastrous play is that they were not losing at the time when they chose to give up on defense. In fact, the Suns actually had a two-point lead before Horford’s shot.

Boston ended up winning but if Phoenix had shown more interest in defending and doing simple things like closing out to shooters or boxing out, it could have been the difference and we may be talking about one of their best wins of the campaign. 

But instead, it was another loss for the Arizona-based franchise and if they continue to show this lack of effort throughout the year, they will be in for many more.