Opening Tip: The impact of Shumpert

Every weekday throughout the season, ESPNNewYork.com will tackle a burning question about the Knicks in our "Opening Tip" segment.

Today's Burning Question: How critical is Iman Shumpert's return?

During the Knicks' Eastern Conference-best 18-5 start, there have been a few glaring holes, including rebounding and interior defense. The absence of Amar'e Stoudemire and Marcus Camby is a big reason why.

But there's something else that needs to be corrected, which hasn't been discussed as much: Opposing guards are going off on the Knicks.

Here's a running list since the start of the season: Jrue Holiday (27 points), O.J. Mayo (23 and 27 points), Tony Parker (19 points and 12 assists), James Harden (33 points), Brandon Knight (21 points), Deron Williams (16 points and 14 assists, and 18 and 10), Kemba Walker (25 points and 11 assists), Marco Belinelli (22 points) and Ty Lawson (23 points).

Most recently, Kyrie Irving scored a career-high 41 points on Saturday night.

Overall, the Knicks' perimeter has done a nice job collectively on defense, rotating and closing out on shooters. While Knicks' opponents are shooting 66.4 percent at the rim -- fourth-worst in the NBA -- they're shooting below 40 percent, even as far down as 33 percent, from every distance away from the basket.

But where the Knicks -- especially Raymond Felton -- are struggling a bit is guarding isolation and pick-and-roll plays featuring top guards. Case in point: Felton couldn't contain Irving in the first half, so Mike Woodson switched Jason Kidd on him. Kidd gave everything he had to ball hawk Irving, but obviously the Cavaliers' budding star was too young and too good for the 39-year-old to keep up with.

So where does that leave the Knicks? In the hands of the 22-year-old Shumpert, who on paper is the team's best on-the-ball defender. But, of course, he's recovering from a serious knee injury. If he gets back to where he was, though, "The Rook" will be a "big piece to the puzzle," as Woodson always says, for the Knicks.

It will be interesting to see how the Knicks' starting five shapes up over the next month or so. Will Shumpert and Stoudemire be in the first unit, replacing Kidd and Ronnie Brewer? Woodson has his work cut out for him, to come up with a rotation that enables the Knicks to start strong, and continue their offensive balance and defense needed to maintain leads and wins.

The real Knicks season may not have even started yet.

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