Depleted Knicks suffer sloppy loss to Suns as downward spiral continues

This is more than a rut.

The Knicks are beginning to spiral, as evidenced by Saturday’s 106-99 loss to the Suns at Madison Square Garden.

In a sign of just how poorly things are going for them at the moment, they went on a 16-0 run to go up by 10 points in the third quarter, but they still managed to end the quarter down three.

That’s because, after one of their best stretches in weeks, they let Phoenix close the period on a 13-0 run and undo all the good that they had done.

That’s the way it’s been recently for the Knicks: too many bad moments outweighing anything positive.

Yes, they were without Jalen Brunson and Josh Hart, both sidelined with right ankle ailments.

But the Knicks had more than $134 million in firepower on the court in Karl-Anthony Towns, OG Anunoby and Mikal Bridges. But it’s hard to commit 17 turnovers and shoot as badly as the Knicks did and win.

So the alarm bells only ring louder by the end of the night as they dropped to 2-8 in their past 10 games and 7-10 since winning the NBA Cup. They’ve gone on a four-game slide and their current three-game losing streak since winning the in-season tournament.

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It’s not just the dog days of the season. This is a prolonged stretch.

Devin Booker, returning after missing one game with his own ankle injury, hurt the Knicks with 27 points.

Collin Gillespie made the Knicks dizzy in the fourth quarter, scoring eight in the period as the Suns pulled away.

And Phoenix got strong production from their bench, with Grayson Allen and Jordan Goodwin adding 16 and 13 points, respectively. In total, the bench outscored that of the Knicks 39-14.

There has been so much talk recently about the lax Knicks defense. But it wasn’t the biggest problem Saturday. They shot just 40 percent from the field on offense and had a nine-point disadvantage in points conceded off turnovers. It was the fifth game since Jan. 1 they’ve scored 107 or fewer points. It’s the third time they’ve scored fewer than 100 in that stretch.

Towns, Anunoby and Miles McBride’s final numbers look OK — they finished with 23, 21 and 23 points, respectively. But they went quiet in the fourth quarter, during which the Knicks were outscored by four points.

Down by seven with just over a minute left, Towns had a wide-open three from the top of the key, a chance to cut the deficit to four and make it interesting. But he barely hit the rim. It was fitting, and the MSG crowd let him hear it.

The Suns entered Sunday fourth in the NBA in offensive rebounds per game. Without Hart, the usual Knicks advantage on the glass went missing.

During a five-minute stretch in the second quarter, the Suns grabbed four offensive rebounds and converted them into nine second-chance points. They finished with a four-point advantage in second-chance points.

The Knicks left the West Coast with Draymond Green taunting Towns as a lasting image.

And now, they began a homestand with boos raining down as the game came to a close.