Halftime Report: Celtics 53, Knicks 49

The first 24 minutes of the Knicks-Celtics first-round series are in the books. Both teams played well defensively, forcing each other to shoot shots at the end of the shot clock -- but when they did, they mostly connected. While the Knicks shot 46.2 percent from the field, the Celtics were even better -- 52.6 percent.

Carmelo Anthony scored 19 points for the Knicks, but Jeff Green had 20 for the Celtics, shooting 7-for-10 from the field. Anthony was 6-for-15, over-dribbling and forcing too many contested shots as the Knicks' offense became stagnant in the second quarter.

Here are four other observations at halftime:

1. Delayed defensive rotations. This was especially the case when the Knicks' doubled down on Green, Paul Pierce or Kevin Garnett. That created several opportunities for the Celtics to swing the ball quickly around the perimeter to the 3-point shooter in the corner, with a Knicks guard scrambling to cover from the block. In addition, on two occasions midway through the second quarter, the over-attention paid to the Celtics' low-post player enabled Avery Bradley (11 points) to slice through the paint and score on layups.

A key issue was the Knicks' help defender -- sometimes J.R. Smith, other times Raymond Felton -- turning his back to his perimeter player when the Celtics had the ball in the low post. The Knicks' positioning and court awareness need to improve in the second half.

On a positive note, Iman Shumpert's extra pressure down low came in handy on one play, when he deflected a pass intended for Garnett and then hit a 3-pointer on the other end. His backcourt teammate, Felton, was also effectively defensively. He had two steals beyond the arc, and a block on a Bradley jump shot.

2. Emotions not all the way in check. Against the physical and trash-talking Celtics, it's going to be key for the Knicks to remain focused despite the additional bumps and bruises. There were two times in the first half when Anthony and Tyson Chandler lost their cool a bit. On one possession in the first quarter, Chandler gave an extra, unnecessary push to Garnett after a whistle, which resulted in the center getting called for a technical foul.

Later, at the end of the first quarter, after Anthony went up for a layup and thought he deserved a call, while he was complaining to the referee, his defensive assignment (Green) connected on the other end for a buzzer-beating 3-pointer. That enabled the Celtics to lead after the opening quarter, 29-26.

3. Significant screening. One of the most overlooked aspects of Chandler and Kenyon Martin is their screening ability. They both returned to the lineup after finishing the season injured. Combined with their timing, toughness and well-placed stance on defenders, they're able to crate space for shooters. In the first quarter, Anthony, Smith and Felton were able to get open. In fact, on one Martin pick for Smith, the sixth man was able to get inside the paint and throw down a nasty one-handed dunk.

4. Big bench boost. The Knicks were 6-for-10 from 3-point range, and Smith and Jason Kidd accounted for three of them. Smith continued to attack the paint as he did late in the regular season. He had 11 points off the bench.

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