When I first saw J.R. Smith's elbow connecting with Jason Terry's chin, my initial thought was that a flagrant foul, penalty-two was excessive. In live action, and on most replays I saw, it looked like Smith was annoyed with Terry's pesky defense when he tried to clear space with a rip move -- but it also looked like Terry flopped and made it look worse than it was.

Terry may well have flopped, and he may well have made Smith's elbow look worse than it was. But that didn't excuse Smith's obvious intent, and it didn't make the one-game suspension that came down from the NBA office on Saturday any less inevitable or justified.

This clip -- when they go to the slow-motion close-up -- shows how Smith sized up his target, flexed with all his strength, wound up and delivered an obviously intentional blow to Terry's head.

Then, of course, Smith dropped the ball and strutted away, the way someone who's guilty would do.

Two other subsequent aspects of the play also sealed the outcome: 1.) The way that Terry anticipated the contact meant that he knew what to expect at that particular moment from Smith, who, let's be honest, has been known to make questionable decisions; and 2.) Celtics coach Doc Rivers' reaction -- pure horror and concern for his player -- was an easy tip-off that Smith's move was not an accident.

There are unwritten rules of basketball combat. You don't invade a jump-shooter's landing space. You don't drill a driving player while he's in the air and defenseless. You don't purposely hit someone in the head.

You also don't try to steal the ball from a player who is obviously slow-walking the ball across the halfcourt line with the intention of calling a timeout, as Patrick Beverley did to Russell Westbrook. But that's another story.

(Of course, that didn't stop Kevin Durant from trying to return the favor to Jeremy Lin on Saturday night. This is another unwritten rule that the NBA is going to have to find a way to start enforcing.)

So Smith will miss Game 4 between the Knicks and Celtics and deservedly so. You can't elbow someone in the head with concussion concerns so paramount in contact sports, and you certainly can't elbow someone in the head on purpose and get away with it.

Ask Rip Hamilton, who did this to DeMar DeRozan a couple of weeks ago and also was suspended for one game.

Thankfully, nobody got hurt in either case. It's no solace for the Celtics, however, that this was about the only good thing that has happened to them in their first-round series against the Knicks.