Boston's need for a rim protector is becoming more and more blatantly obvious.This is the second in a (hopefully) long series of posts detailing Boston’s in-game sets and adjustments during the playoffs, featuring a positive and a negative from each game.Positive: Hand-off plays sparking penetrationOk, so by “hand-off plays sparking penetration,” I meant to say it in the singular. As in “one hand-off play sparked penetration.” This one, right here:Cut me some slack: It’s a little bit difficult to find positives after that abominable second half. But let’s take a closer look at this particular set, since it’s one of the only plays that ended in a shot attempt around the rim and showed the Celtics getting any kind of penetration against New York’s defense. The play began with Avery Bradley bringing the ball up the court on the left side and passing it to Brandon Bass in the middle. Bass then dribbled to the left side, and Jason Terry cut back around him, receiving what amounted to a triple screen from Pierce, Bradley and Bass.The Knicks were able to easily switch because they were playing their super small-ball lineup, which meant that Iman Shumpert, Raymond Felton and Pablo Prigioni were all, to a certain extent, interchangeable. Prigioni switched off Bradley on the second screen and followed Terry out behind the 3-point line, fighting through Bass’s screen and seemingly knocking the play off-kilter.But Terry seemed to have been a misdirection, because Bradley immediately turns and cuts back around Bass, receiving the hand-off and driving to the hoop.Bradley drives against Chandler and puts up a layup that gets swatted away (viewers disagreed as to whether it was goal-tending (it was totally goal-tending)), but it was one of the rare times that the Celtics got into the paint without crashing into someone. The Celtics only used two hand-off plays, according to mySynergySports, and one of those plays was actually a pass to Kevin Garnett for, you guessed it, a mid-range jumper. After Rondo’s injury, the Celtics have used this tactic on occasion to get penetration against tough defenses. It might be time to put a little bit more emphasis on it, especially since Jeff Green struggled to get himself going in Game 2.Boston has always been a team that lived and died by the jumpshot, but when they exclusively shoot jumpers, there’s going to be a lot more dying and a lot less living.Negative: Pick-and-roll defense on Raymond FeltonMuch has (correctly) been made of Boston’s lack of rim protection, and nobody has taken advantage of this more than Raymond Felton. This is aggravating to say the least but not entirely unexpected. New York has the second best pick-and-roll ball-handler offense in the NBA, at 0.86 points per possession (per Synergy), but last night the Knicks managed 1.18 PPP on 8-14 shooting from the field.One of the reasons the pick-and-roll works so well for New York is the way the bigs setting the screen dive to the hoop after they set the screen. We saw this early on as Tyson Chandler set a screen for Felton and dragged Paul Pierce to the hoop with him, stranding Chris Wilcox on Felton. Felton gets around Wilcox with relative ease and scores.The best way to beat this strategy is to go under the screens, since Felton is much less dangerous as a jumpshooter (34% from 3-9 feet, 24% from 10-15 and 37% from 16-23, per HoopData.com) than he is at the rim (57% per HoopData). As you can see from the following videos, even the shots that go in are more difficult because Boston’s defenders saw the pick coming and went under.Perhaps the biggest surprise is in the second video when even Avery Bradley is ducking under the screen, something he doesn’t tend to do very often. It should be noted that it’s not that Boston doesn’t respect Felton’s jumpshot (although it’s possible they don’t), it’s that they don’t have anyone who can stop a ball-handler at the rim, so they’d rather give up the open jumper. From an efficiency standpoint, this makes some sense. It’s not an ideal strategy by any means, but at this point, so many of the Celtics’ strategies are stitched-together makeshifts that this one fits right in.In ConclusionThat was an ugly game with a lot of ugly conclusions to be drawn. One would like to hope that aspects will be cleaned up when the series shifts back to Boston, but if the Celtics can’t get to the rim or make adjustments to limit New York’s pick-and-roll game, this series is going to be over fast.Follow Tom on Twitter: @Tom_NBA.