Knicks' perimeter D has been the difference

The Knicks' perimeter defense has been a weapon for them throughout the season. Douglas Jones/US Presswire

Through their 7-1 start, the Knicks are the top defensive team in the NBA, holding opponents to 90.0 points per game.

ESPNNewYork.com decided to dig into the numbers to see how they've been doing it, and this is the main takeaway: While they're preventing players from getting inside, they're forcing opponents to shoot outside jumpers -- and based on contesting and strategic rotations, with some luck mixed in, their opponents are missing.

Here are four key elements of their suffocating perimeter defense:

1. More jumpshots, less layups: While opponents are shooting 63.7 percent in the restricted area -- the Knicks are a bit undersized down low with Carmelo Anthony at the four -- they're rarely allowing them to get in that space. They're giving up the fewest field goal attempts in the restricted area (190), and the ninth-fewest points in the paint per game (38.8). That's because the Knicks' perimeter defense has been airtight. Looking ahead, if opponents can figure out how to break through more often -- which the Grizzlies did by pounding the ball inside Friday night -- that could pose a problem, especially exposing Anthony to foul trouble. But hopefully for Knicks fans, if that does happen, Marcus Camby and Amar'e Stoudemire, when he returns, will provide more of a defensive punch down low.

2. Causing bricks: The Knicks are forcing a league-best 31.5 and 30.6 percent on jumpers and catch-and-shoot Js, respectively. What's interesting is that opponents are shooting 29.8 percent on unguarded outside shots. That number suggests the Knicks are rotating on the perimeter effectively to leave weaker shooters open. Of course, they're also fortunate there's been more clanks than swishes.

3. J.R. Smith and Ronnie Brewer's impact: The two wing players have been making the biggest difference, based on the time they've been on the court. When Smith is playing, the Knicks are holding opponents to 10.4 fewer points per 48 minutes; and when Brewer is playing, the team is holding opponents to 6.1 fewer points. Also when they're on the court, opponents are shooting worse from the field and 3-point range and committing more turnovers. Overall, the Knicks' two best defensive lineups include Smith and Brewer.

While Brewer has excelled at rotating and forcing players to pass back out, Smith has been the Knicks' best individual perimeter defender, as he's been holding opponents to 34.9 percent shooting in one-on-one situations (post-ups, spot-ups, isolations and pick-and-rolls). With Felton and Kidd being average individual defenders -- they've been picking up steals more from traps and help D -- Smith and Brewer have helped close the gaps around the arc. Iman Shumpert, when he returns, should do so even more.

4. Pablo Prigioni and Rasheed Wallace's underrated D: When Prigioni is playing, the Knicks are holding opponents to 8.9 fewer points per 48 minutes; and when Wallace is playing, the team is holding opponents to 5.7 fewer points. Prigioni, in fact, is part of the best two-man defensive lineup on the Knicks. When Prigioni and Brewer are on the court together, the Knicks are holding opponents to 63.9 points per game per 48 minutes.

As for Wallace, listen to this: Out of the 218 players in the league who have defended at least 50 plays, he's held opponents to the second-lowest field goal percentage (26.3). Sheed has stepped in nicely for Camby and Stoudemire; the Knicks just need more of an interior presence, especially against frontcourt-oriented teams like the Lakers and Clippers.

For now, the Knicks have basically sealed the perimeter shut.

Research assistance: Ryan Feldman, ESPN Stats & Info

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