Christmas Countdown: Knicks-Celts W2W4

Fans waited patiently [or not so patiently] through a 149-day lockout for this: the opening tip of the 2011-2012 NBA season.

The Knicks will get things started with a home game against the Celtics on Sunday. Boston swept New York in the first round of the playoffs last season, but Doc Rivers brings a different cast of characters into the Garden on Christmas Day. No Jeff Green, no Glen Davis, and the "Big Three" are a precious year older.

The Knicks, of course, have issues of their own: an unsettled situation at point guard, and the challenge of adding new pieces like Tyson Chandler and Mike Bibby in a shortened training camp, just to name a couple.

With that in mind, here's a look at what to watch for on Sunday:

MEN IN THE MIDDLE: With the Celtics lacking a game-changing talent at center (Jermaine O'Neal and Greg Stiemsma are their current options at the '5'), it will be interesting to see what kind of impact Chandler has in the middle. Chandler was brought in specifically to lift the Knicks out of their defensive doldrums -- on average, they allowed opponents to score more than 45 points in the paint last year and were out rebounded by 3.5 boards per game. We get to see how Chandler changes the defense for the first time on Sunday.

POINT, COUNTERPOINT: One of the biggest question marks for the Knicks coming into the season is this: Who will settle in as the starting point guard? Toney Douglas is penciled in as the starter, but much of the uncertainty over Douglas' ability to handle the role stems from what he did in the 2011 playoffs. Simply put, Boston's Rajon Rondo ate him for lunch.

In the three games Douglas started in place of the injured Chauncey Billups, the Knicks were outscored by 41 points with Douglas on the floor. Rondo averaged 22 points and 13 assists in those three games.

Can Douglas -- who is generally known as a talented perimeter defender -- do anything to slow Rondo on Sunday? Mike D'Antoni and assistant Mike Woodson need to come up with a creative way to stymie the Celtics' lead guard.

CAN AMARE AND CARMELO COEXIST? There were times last season where Amare Stoudemire and Carmelo Anthony didn't exactly look comfortable on the floor with one another. Sure, they both finished in the top six in the league in scoring, but Stoudemire's average dipped nearly three points per game after Anthony arrived. Both players have downplayed any questions about their chemistry during the preseason. The normally affable Anthony stated that he flat-out didn't want to entertain questions about the subject earlier in training camp.

Of course, Anthony and Stoudemire can put the topic to rest by developing a cohesion in D'Antoni's half-court sets. We'll see if they start off on the right foot on Sunday afternoon. Also, if Paul Pierce doesn't play, it will be interesting to see if the Knicks can take advantage on both ends.

ROOKIE WATCH: Rookies Iman Shumpert and Josh Harrellson have impressed their teammates and the coaching staff with aggressive play during the preseason. Will that continue when the curtain comes up for the regular season? Shumpert, and to a lesser degree, Harrellson, are expected to play pivotal roles on the second unit.

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