The Boston Celtics moved to 4-1 on the season with a 104-102 (box score) win on Friday over a gutty Knicks team that just wouldn't go away down the stretch. Jayson Tatum was the hero with the game-winning shot, but it was Brad Stevens' simple-but-smart play design and the Celtics' multi-threat roster that made it possible. 

It went down like this: With 4.7 seconds left, New York's Marcus Morris hit his former team with a 3-pointer to tie the game at 102, setting up the Celtics with a sideline out of bounds coming out of a timeout. Stevens is known as one of the best play designers in the league. He manipulates switches. He misdirects. But on Friday night, he kept things very simple. 

As you'll see in the video below, he positioned Kemba Walker deep in the backcourt, set a simple cross-screen for Tatum, who took a pass with his back to the hoop and simply made a one-on-one move for a contested 21-footer. It was the odd last-second shot that both the offense and defense were happy to accept. Before we get more into the breakdown of this play and what it says about the weapons at Stevens' disposal, let's have a first look at how it played out. 

Again, as you can see, Walker is set up some 75 feet from the basket to start. Walker is Boston's best player. He had 33 points on Friday and was in a great rhythm down the stretch. That he would at least be involved in the final action, if not Stevens' choice for the last shot, seemed only logical. Even Celtics color man Brian Scalabrine, upon seeing the initial setup, surmised that Walker was surely preparing to get a running start so he'd be going downhill when he got the pass. 

But watch the video again. Walker has no intention of being any part of this action. His whole purpose is to take the man defending him, in this case Frank Ntilikina, completely out of the play. After that, notice that Knicks big man Mitchell Robinson is guarding the inbounder, which is a predictable defensive setup given Mitchell's length to harass the passer. Add it up, and before the ref has even handed the ball to Marcus Smart to make the inbound pass, New York's two best defenders have been eliminated. 

That leaves the Celtics, essentially, in a game of 3 on 3 with Tatum and Gordon Hayward being pretty equal threats to take the last shot. That's the beauty of this Boston roster. There are so many interchangeable perimeter players, all with the ability to create their own shot, that Stevens doesn't have to trick the defense with some intricate design to get a good look. He just has to get one of his numerous last-shot options -- Tatum, Hayward, Walker, Jaylen Brown, or even Smart -- the ball in enough space to make a one-on-one play. 

On Friday, it was Tatum. who had it going all night with 24 points on 4-of-8 shooting from three. Walker was the only player who was having a better game, which made him the perfect decoy. Had Stevens put Tatum in the backcourt, the ball obviously would've been going to Walker. Unpredictability is the foundation of all great last-shot plays, and Stevens, by virtue of his reservoir of similarly skilled perimeter weapons, has that advantage built in before his pen ever hits the whiteboard. 

On Friday night, Tatum got the call. Walker hardly moved, and Hayward simply went through the motions after he cross-screened for Tatum. Still, the Knicks were in good defensive position. R.J. Barrett had Tatum one-on-one in the corner with his back to the hoop. But Tatum is in space, and when a great shot-creator is in space, he always has the advantage. That's all Stevens was looking for. An advantage. From there, as they say, it's a make-or-miss league, and Tatum made it. Simple as that.