The other one is left behind in case of injury, presumably to feast on nachos and prepare a hanky to mop Joey Crawford's brow at halftime.
The concept makes sense. The game is difficult enough to officiate with three referees, let alone to work shorthanded when an injury reduces the workload to a two-man game.
Yet lately, it sure seems like an extra set of eyes, a fourth pair, might just help.
So put the nachos down, let Joey mop his own brow, and get down to the business that most NBA fans are involved in on a nightly basis these days — watch the games on TV.
Sometimes the best view of a game is the one that comes courtesy of countless camera angles.
So if there is a fourth referee in the building, one that rated high enough during the regular season to earn the trip and per diem, why not put him to work? Why not station him in the TV truck, where he can see all the angles that a mere six eyes on the court might miss? Why not provide an instant line of communication to the scorers' table?
Would it mean that games then would become officiated differently than during the regular season? Aren't they anyway?
It certainly is not unprecedented to change the rules during the playoffs. The NFL and NHL do it with their endless overtimes. Major League Baseball commissioner Bud Selig decided during last year's World Series that games on that level no longer could be shortened by weather, but rather would instead remain in indefinite delay if needed.
These are the playoffs. The rules are different. Every ruling matters.
It is one thing for officials to stand at a monitor at midcourt in front of unruly fans and carping coaches when it comes to determining 3-point shots, buzzer-beaters and flagrant fouls.
It is another, away from any swaying influences, to get it right. Clearly, the flagrant-foul rulings haven't even been close, at least in the eyes of the league office.
For as second-tier as the NHL might be viewed, it gets it right by making its goal-or-no-goal decisions out of the collective calm of the league office.
These are big decisions, on the biggest stage of the season.
Consider, for example, flagrant fouls. The league does a credible job of reviewing such plays and making things right. But those after-the-fact decisions, such as the reversal of Anthony Johnson's Game 3 flagrant foul against Mo Williams, do nothing to remove the two points scored at the foul line.
Ditto for Kobe Bryant not getting two foul shots when the league decided Dahntay Jones, indeed, did not stick his foot out by accident.
Then consider all the calls the camera has gotten right that the on-court officials simply missed.
J.R. Smith sneaking into the jump-ball circle before the ball had been tipped? Chauncey Billups stepping out of bounds before nailing a 3-pointer? Andrew Bynum's swipe at Chris Andersen that was ruled flagrant but clearly was an on-ball play?
That's just all from one series.
Then there was Williams throwing the ball at Dwight Howard in Game 2 of Magic-Cavaliers, where the three referees seemingly were the only ones in the building who missed the sequence. How could a fourth set of eyes possibly have hurt there?
Yet which would take longer, those incessant referee huddles at midcourt to sort matters, or a top-tier NBA official sitting in a state-of-the-art TNT or ESPN truck shouting, like the game director, "Camera 1! No, give me Camera 2 and slow it down! Do you have anything from the baseline?"
Boom. Boom. Boom. And, potentially, far more accuracy than three referees trying to recreate what they just saw or thought they saw.
The thing is, it hardly would be unique. The NCAA has been reviewing every play at its top level of football for years. Imagine that, constant review, making perfection the goal.
The argument against such replay intrusion has been the natural flow of the game. Uh, have you been watching Magic-Cavaliers or Nuggets-Lakers? The actual dunking and running have come as mere interludes to free throws.
It is insanity that Marv Albert or Mike Breen, within seconds of whistles, can turn to their analysts and say, "Well, they might have missed one there," when the NBA can arm itself with the same replay option, with its own rules expert already on hand.
For all the consternation about replay intruding on the "human element" of officiating, does anyone ever complain when technology helps get things right?
The contrasting argument is that by allowing technology to serve as a backup, officials might grow lax, allowing the camera to clean confusion. It is the same tired argument offered when the league moved two decades ago from two to three referees, that there would be less vigilance, with a backup view added to the equation.
Whether right or wrong, the chorus is increasing, led by the loudest of loudmouths.
"We've got to have a conversation when the playoffs are over about the officiating," Charles Barkley preached from his TNT pulpit. "I love the officials, but the officiating during the playoffs has not been very good. It's been terrible officiating."
Said postseason postgame partner Reggie Miller, "I think the rules committee needs to get together and expand replay."
That's the rub. The league already has expanded its officiating presence during the playoffs.
Just because that extra official is out of sight doesn't mean he has to be out of mind. Let the three referees on the court know that someone in the building has their back. Let them know that the fourth wheel of their crew is ready to roll.
Four-thought should be the answer.
PBT: San Antonio executed its game plan well in Game 1, shutting down Grizzlies star Zach Randolph.
PBT: Spurs guard Tony Parker repeatedly sliced through the Grizzlies' defense, creating 20 points and nine assists in an easy Game 1 win for San Antonio.
Take a look at photos from the playoffs, including the Magic finishing off LeBron and the Cavs in Game 6.
Video: NBA from NBC Sports
Grizzlies ready for 'running' Spurs
DPS: Lionel Hollins tells us how he plans to play against the San Antonio Spurs in the Western Conference finals.
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