Jeff Green of the Nets puts up a shot for a...

Jeff Green of the Nets puts up a shot for a basket during the third quarter against Nerlens Noel of the Knicks at Barclays Center on April 5. Credit: Jim McIsaac

PHILADELPHIA — As the Knicks fell apart Sunday night at the Garden, watching helplessly as the Cleveland Cavaliers rained down three-point field goals on them, there was a disturbing feeling, but also a familiar one.

While the Knicks have made their way through their first 10 games it has been with an uncharacteristic flaw for a Tom Thibodeau-coached team. After ascending to the No. 4 seed in the Eastern Conference last season behind a hard-working, defensive-minded unit, the Knicks set out to improve their offense in the offseason.

But any expected dip in the defensive prowess pales in comparison to what actually has happened. The Knicks rank 27th in the NBA in defensive rating after finishing third last season. They are last in three-point field goals allowed — 14.9 per game — and rank 23rd in three-point percentage by opponents, who have connected at 36.3%.

"The thing is we know we have to play better, got to play harder, got to challenge shots better," Thibodeau said. "That’s the big thing. They made some tough ones. When you look at film, some of them we could have challenged better than we did.

"We have to play with that edge. Sometimes a player can make a tough shot. We’ve said it many times. You can’t get to the NBA without being a great player. Every player is capable of having a big night. There’s a big difference between a challenged shot and an unchallenged shot. It’s important to challenge shots."

Sunday was a low point as the Cavs connected on 19 of 35 threes, including 13 of 17 in the second half. Ricky Rubio had a career night, hitting 8 of 9 attempts beyond the arc as he scored a career-high 37 points. But it was just as disturbing to see the players around him who found themselves wide-open in the corner at crucial moments as the Knicks attempted a comeback.

After the game Sunday Thibodeau talked about the defensive failings and said, "It’s hard to judge. Whatever the game plan is there’s two things you always look at. One is are you executing the scheme correctly? Two are you doing it hard enough? Sometimes the answer to that is you are. And that’s when you change. If you’re lacking in execution of scheme or intensity, it just takes one person to miss. We’re all tied together. We have to fix it, look at it and learn."

With a day to look at the film, he realized it was both.

"Yeah, both," he said. "There’s things that we did well where they made shots. There's things that we didn’t do as well as we could have. And so that’s what we have to fix."

It wasn’t just the Cleveland game though. The Knicks surrendered 16 of 43 from beyond the arc in Milwaukee Friday. In the game before that Indiana hit 16 of 41 attempts. Before that it was Toronto beating the Knicks at the Garden with 14 three-point field goals.

"Being ready to play is a big part of winning in this league," Thibodeau said. "The games keep coming. Regardless of what happened the previous night, you have to bring that energy every night and get yourself ready to play. So I think that’s the biggest challenge. Sometimes the schedules in your favor and sometimes it’s not. So your defense, your rebounding, keeping your turnovers down, that puts you in position to win. We can’t let go. We have to fight. Some nights things don’t go well, but you still can win. That’s the most important thing."

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