Can the NBA coach's challenge survive its inherent subjectivity, distrust and strategy issues?

After officials upheld Toronto Raptors wing OG Anunoby’s charge against still-shuffling Boston Celtics star Kemba Walker on the fourth night of the NBA season, Raptors coach Nick Nurse said from a TD Garden hallway, “I’m 0-for-2 on challenges, and I can’t believe it. I don’t have any idea what I’m doing here. Zero.”

It took seven challenges, but Nurse finally got a call overturned — a phantom foul against Los Angeles Lakers superstar LeBron James, no less. The coach of the reigning champions hugged his staff and a Lakers fan in celebration. In between, 18 coaches overturned calls. Nine more have succeeded since. Only New Orleans Pelicans coach Alvin Gentry and Denver Nuggets coach Mike Malone have yet to win a coach’s challenge. Both are 0-for-4. On the whole, coaches have won 44 percent of their 190 challenges to date this season.

“You see it gradually going up, so I think they are making improvement on successful challenges,” Joe Borgia, the NBA’s senior vice president of replay and referee operations, told Yahoo Sports of the rising success rate for coaches over the season’s first six weeks. “Now, the hard thing about it is, just because they were successful doesn’t mean it benefited them. ... So, I can’t imagine how difficult it is on them.”

Yahoo Sports reached out to all 30 teams seeking input from coaches on their feelings about the challenge through the first quarter of its inaugural season and the strategies they are using to maximize it during this trial campaign. Most declined to go on record, some of whom have publicly denounced it. One coach threw his endorsement behind the newly implemented tactic: NBA Coaches Association president Rick Carlisle.

“I believe that any time you have a mechanism that could potentially correct an error in an NBA game that it’s a positive thing,” the Dallas Mavericks coach told Yahoo Sports. “I believe it protects the integrity of the competition, so I like the rule, and I believe as time goes on more and more people will feel the same way.”

Multiple coaches, however, have yet to see the benefit of the challenge. Asked what improvements he might make, Golden State Warriors coach Steve Kerr said, “I would tweak it by getting rid of it altogether.

“In fact, I would get rid of all replay if it were up to me, because these stoppages in play just aren’t good for the game,” Kerr told Yahoo Sports. (FYI: His five successful challenges so far trail only Boston Celtics coach Brad Stevens.) “I’d rather see a good flow in the game. We stop the game for so many reasons, and yet even with replay, we don’t get all the calls right. It’s impossible to get all the calls right in the NBA. It’s such a fast game, and there are so many bang-bang calls that could go either way, so even with replay you see plays on tape all the time that you think you got a raw deal on. In my mind, there should be no replay.

“We should just live with the results,” added Kerr. “That’s what we did for however many years before replay came around. It gives a better flow to the game, and in the end I honestly don’t think I’ve ever been in a situation as a coach or a player where I thought a ref’s call cost us the game. There are 100 possessions in a game, so I think we’re trying to be too cute with replay, and I’d rather get rid of it altogether.”

The Houston Rockets might beg to differ. They are reportedly considering a protest of Tuesday’s double-overtime loss to the San Antonio Spurs after officials disallowed Mike D’Antoni’s challenge of James Harden’s regulation “missed” dunk, which clearly passed through the net. Of course, the Spurs could counter with a missed call from earlier in the game that could have also altered the course of the remainder of the game. It can be an endless cycle, and some wonder whether a single challenge is worth the trouble.

To challenge or not to challenge

Coaches are still developing strategy around the challenge, and even then they can be at the mercy of a referee’s interpretation of a foul. Or, a challenge can overturn a goaltend to a block, but your opponent retains possession and knocks down a three-pointer, so you lose a point. You might win an out-of-bounds challenge, but a failure to score on the ensuing play leaves nothing to show for it beyond another stoppage.

Miami Heat coach Erik Spoelstra recently went so far as to describe the entire process as a waste of time. “To me, it hurts the flow,” the two-time champion told reporters prior to a late-November game against the Philadelphia 76ers. “It’s just another thing to focus on that’s distracting. It has nothing to do with the game.”

Yet, it remains a part of the game, at least until the competition committee and board of governors review it after the season. So, coaches are forced to chart when best to issue their lone challenge. Varying degrees of research went into game-planning for it. One Eastern Conference coach said he just uses it when he gets the chance and moves on, assuming an overturned call at one point in the game is as good as any other.

The loss of a timeout is the chief concern among coaches, which is why some have burned their challenge before being charged with a mandatory TV timeout. (The home and road teams are automatically charged a timeout if they have yet to call one by the seven- and three-minute marks of each quarter, respectively.) Coaches are also feeling out which players are more reliable when they start twirling their finger for a replay.

“The coaches are learning which players are more emotional,” said Borgia. “The more emotional players are going to be the ones they’re going to think twice about versus the cool, calm ones. I was on the court for 10 years, and I swore I saw something, and then went to the videotape and went, ‘What the hell was I looking at?’ You don’t even realize it. It’s been an adjustment, and clearly everyone is adjusting, from the coaching staff and whoever they selected to help them with the challenge to the officials and how we review it.”

Ideally, a coach will employ the challenge when he can either confirm or erase a three-point shot (or four-point play) at any point in the game, on a potential momentum-swinging call during the course of normal action and/or in a crucial late-game situation. Kerr successfully challenged a third personal foul called on Stephen Curry early in the second half of an October game against the New Orleans Pelicans, avoiding foul trouble for his superstar. But waiting for the perfect situation also runs the risk that it just never occurs.

“There actually is a lot of strategy,” said Kerr, “but we just might not know the best strategy yet.”

“Generally speaking,” he added, “you want to save it for a big moment in the game, so more likely use it on a three-pointer for the opponent rather than a two-point shot, but to be honest we’re still all kind of figuring it out.”

“It’s completely situational,” Carlisle told Yahoo Sports. “The situations are wide-ranging. We’ve used challenges in the first half, we’ve used them in the second half, and we’ve used them late-game. A lot of it is feel, and as this goes on, we’re all learning the types of situations it makes the most sense to challenge.”

Stevens entered the season with a plan. “There’s a lot of strategy and preseason work that went into it,” he told Yahoo Sports. “We reviewed situations in the past where it could have been considered, and showed our guys when it’s advantageous and not, and why we can’t use it on a whim. The loss of a timeout is the killer, so you either better be right or you better have enough timeouts.” But, by December, Stevens looked to be mouthing to assistants on the sidelines, “I’m done with these f---ing challenges. This is unbelievable.”

This was after Stevens won a challenge. He wanted officiating crew chief Josh Tiven to review a blocking foul against Celtics forward Grant Williams, believing New York Knicks counterpart Julius Randle committed an offensive foul. Tiven overturned the blocking foul, but to a no-call, counting the resulting Randle layup.

What is and what isn’t ‘tied to the play’?

It was the latest in a string of maddening challenge results for Stevens, including this season’s premier examples of the subjectivity of personal fouls and imperfection of challenges. With less than three minutes left in the fourth quarter of a game the Celtics led by six, Los Angeles Clippers star Paul George pushed off against Daniel Theis to gain separation on a drive, took two steps and drew a touch shooting foul from Jaylen Brown. Stevens challenged the call. Crew chief Marc Davis upheld it. The NBA’s explanation? The push-off was not tied to the play. George made one of his two free throws, and Boston lost in overtime.

Two games later, Stevens challenged a shooting foul called on Celtics center Enes Kanter on a similar drive to the basket by Sacramento Kings forward Harrison Barnes. Crew chief Tony Brown overturned the call against Kanter, instead crediting a non-shooting foul to Brad Wanamaker on a reach-in earlier in the drive, just before Barnes took his two steps to the rim. In other words, Wanamaker’s foul was tied to the play.

So, which is it? Borgia had yet to see the the Barnes review the morning after the Kings-Celtics game (the internet was down at the league office), but the league has tried its best to clearly define these scenarios.

“This is the challenge of replay since we put it in [at the start of the 2002-03 season]: How far back do you go?,” Borgia told Yahoo Sports. “For the coach’s challenge, we have the phrase ‘tied to the play,’ and that is slightly subjective. ... To try to help the referees get more consistency, when we have a drive to the basket and the foul is at the rim ... we say, ‘OK, since he was fouled in the act of shooting at the rim, we’ll let you go back to the start of the shooting motion, and anything illegal from that point is tied to the play.’”

The act of gathering is what is supposed to signal the start of the shooting motion. Problem is, there is some subjectivity in that, too, and the two plays involving the Celtics fall on either side of the interpretation. Therein lies the problem. It is impossible to completely remove subjectivity from these challenges, as Mavericks owner Mark Cuban pointed out when his team was on the wrong end of an overturned foul call.

Or, as Nurse put it earlier this season, “I think that gives a big window to see clearly through.”

There is almost always some contact on shots at the rim, so officials are now left to determine degrees of contact in their reviews. There are some signifiers they can look for — whether the contact impacted the shooter’s speed, quickness, balance, rhythm or path to the basket — but those too are highly interpretive.

“Clear and conclusive evidence to overturn it is a very subjective term,” said Borgia, so Monty McCutchen, the NBA vice president of referee development and training, holds regular crew-chief conference calls to discuss it. “We’re trying to narrow it from a seven-lane highway. It’d be great to get to a one-lane highway, but I think we’re down to a five-lane highway working on a three-lane right now. We’re seeing some improvement everywhere, and I think it’s just going to take a little bit longer to really see the final result.”

Human nature inside a video review

The NBA is committed to making this work as best it can, and Borgia is encouraged that the increasing success rate of challenges signifies progress by all parties in that regard. The league is charting all possible data and considering every internal suggestion. Potential changes to the system are already being tracked should the challenge pass muster with the competition committee and board of governors at season’s end.

Still, there is a larger hurdle the challenge must overcome beyond streamlining its subjective nature, and that is the inherent distrust between players/coaches and officials. Crew chiefs have upheld 95 called fouls on 158 challenges so far. Some players and coaches believe there is a reason those numbers favor the refs.

When crew chief Zach Zarba upheld a foul call against Los Angeles Lakers wing Kentavious Caldwell-Pope, who may or may not have grazed Pelicans forward Brandon Ingram’s elbow, LeBron actually interrupted the ESPN broadcast to tell Mark Jones, Jeff Van Gundy and Mark Jackson and their national TV audience, “When a ref makes that call, he don’t ever want to be wrong. They’re not going to overturn it. Ever.”

“I like the spirit of the rule,” Detroit Pistons coach Dwane Casey told Yahoo Sports. “I like the ability to be able to, especially in crucial situations, challenge a call. But, again, I don’t know if it has an effective value. I have to do some more research. I don't know what the success rate is over the league, but I don't think it's very good. But, it's very difficult to get an official in any league to change his mind when he made that call.”

ESPN’s Doris Burke went a step further in a conversation with colleague Zach Lowe on his podcast.

“I had one coach a few short weeks into the season say, ‘This is the percentage of overturned calls, and when you get one overturned, the next call goes against you, say, 75 percent of the time,’ ” said Burke. “And I was hollering, because a lot of coaches will tell you there’s a human dynamic and these officials don’t want to be wrong. And if you catch them wrong, that next call is going against you.”

Borgia is doing that research, and he disagrees with this sentiment. One data point that supports the integrity of officials in this regard is that crew chiefs overturn their own calls more often than they do those of their partners. Eventually, if challenges survive this season, personal fouls may go to the replay center in Secaucus, N.J., as the out-of-bounds and goaltending calls already do, but the NBA felt it best to leave those judgment calls to their most experience and highest-rated referees, at least during this trial campaign.

“If you miss a call on the court and you sort of know you missed it, you don’t want to go miss another one to try to make up for it, because now you have two errors in the game,” said Borgia. “A referee’s judgment and their job is based on the errors they make. Why would you want to commit more errors? If they can go to video and get the play right, it’s a win-win for them, because if they stay wrong, all the announcers are going to do is talk about it, and you guys pick the stories up and that’s the last thing you want as a referee.

“Trust me, that is not their nature. Now, we’re also human beings, so I can’t sit here and say every ref in the country would do that. We always want to be right, but when you go to video, you better come out right.”

Is this actually worth the NBA’s time?

The final hurdle for challenges surviving this season is what Kerr and Spoelstra, among others, have referenced: The challenge is just one more stoppage on top of timeouts and other replays that disrupt the flow of the game and its entertainment value. And, if this system is still imperfect, is this all worth the time?

Borgia is crunching those numbers, too. The number of challenges has held fairly steady at roughly six every 10 games, although the possibility remains that the number could increase as coaches get more comfortable with the system. A lot of successful challenges have come during TV timeouts, and a majority of the time reviews are completed before the timeout is over, Borgia says. He does not yet know how many times, if at all, a coach has won a challenge, kept his timeout and used all seven of his allotted timeouts.

One concerning time-related statistic that has developed over the first six weeks of the season is the fact that timeouts are up 60 percent from last year. Not all of them are the result of unsuccessful challenges, “but you have to assume the coach’s challenge is some or the majority of that,” Borgia said. “I heard we have had some closer games, which could lead to more timeouts, but 60 percent is a large amount to be up in our business. ... So, now the competition committee and the owners have to weigh what it’s worth.”

There is no hard-and-fast number that constitutes an excessive time overage. As Borgia said, if coaches overturn 90 percent of the calls against them, alter outcomes as a result, and it only adds 30 seconds to a minute on the end of games, that might be worth their time. It may not if coaches are only right less than half the time, as they currently are, and each review adds closer to a few minutes to the viewing experience. It will be on the competition committee and board of governors to weigh those numbers over the summer.

Stevens, Gentry and Utah Jazz coach Quin Snyder are the three coaches currently representing teams on the competition committee, along with three owners (the Charlotte Hornets’ Michael Jordan, Denver Nuggets’ Josh Kroenke and Sacramento Kings’ Vivek Ranadive) and three general managers (the Chicago Bulls’ John Paxson, Philadelphia 76ers’ Elton Brand and Portland Trail Blazers’ Neil Olshey). Both the referees’ and players’ associations are also represented at each competition committee meeting.

Count Burke among those who believe the challenge is already dead in the water, if only due to widespread opposition from coaches. “This will be a one-year experiment,” she told Lowe. “I’d be shocked if this is in place next year. Shocked.” Our canvassing of the league turned up little to dispute that, although Carlisle’s endorsement may keep it on life support, and Borgia sounds hopeful that further narrowing of subjectivity from officials and improved strategy from coaches could breathe life into the system before it is too late.

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Ben Rohrbach is a staff writer for Yahoo Sports. Have a tip? Email him at rohrbach_ben@yahoo.com or follow him on Twitter! Follow @brohrbach

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