Fair Play: SwingVision puts its electronic line-calling to the test in tournament play

"When in doubt, call it out."

That’s the unfortunate philosophy many players use when it comes to line-calling. Tennis is one of the few sports in which the participants also serve as the officials. Players rule on their opponent’s shots, and vice versa.

When honesty is upheld, the system works. However, as anyone who has played competitive matches knows, the stress of competition often tests its integrity. Whether by human error or something more nefarious, getting hooked and arguing line calls is a rampant problem in the game. When a player loses a close match, and the outcome is influenced by questionable calls, there’s no worse feeling.

To remove any doubt, automated line-calling has been a part of the professional ranks for many years. However, up to this point, the cost to install such systems has been prohibitive at amateur levels. The equipment is not only expensive and often permanent, but requires significant maintenance.

SwingVision wants to change that.

The app from the California-based company gained its foothold in tennis tech by using artificial intelligence to provide detailed match stats and highlights all from a smartphone. It then added line-calling to its host of features and has been working to refine its accuracy. It currently gets 97% of calls correct for shots landing within 10 centimeters of line. The human eye is only 90% accurate in the same situation.

To put the technology to the test, SwingVision recently teamed with the USTA’s Southern California section to use its electronic line-calling at four different tournaments at four different sites over the past year. On each court, an iPhone was mounted on a fence behind the baseline on one side of the court which would record the match. That phone communicates with an iPad on a tripod stationed at the net post.

When a player believed an out call was made in error, they could challenge it. Both players would then go up the iPad and watch an animation of whether the agreed upon shot was indeed in or out. Just like the pros, the players got three incorrect challenges per set.

“We are thrilled with the product,” says Maria Goldberg, Director of Competition at USTA SoCal. “Electronic line-calling brings honor back to the game. You can walk away from the match and feel that you got beat instead of cheated. It’s definitely a game-changer for tennis.”

Which was the prevailing sentiment by all involved at these pilot events. The most cited benefit was the overall calmer, more positive atmosphere. Players weren’t at each other’s throats because of perceived bad line calls. Having challenges allowed them to focus on their tennis without the anxiety of whether their opponent was stealing points. It also kept parents and coaches civil spectators, rather than sniping with each other and officials.

“If a player feels they got a bad call, they go right to the unit at the net and it all ends right there,” says Trevor Kronemann, Executive Director of USTA SoCal. “They get a call, whether it was good or bad, and they can move on from there. It doesn’t cost them a game, a set, maybe even a match to get over. Which is good for tennis and good for the players.”

The most recent SwingVision test case was the Dennis Rizza Classic held on eight courts at the Jack Kramer Club in Rolling Hills, Calif. in November. The event pits Division I college players from various west coast schools. If there’s a segment of the game that’s begging for electronic line-calling, it’s collegiate tennis. Shady calls have unfortunately become part of the fabric of the sport, with some of the most egregious moments going viral on social media.

Peter Smith, the general manager and director of tennis of the Kramer Club, knows it all too well. He was a college coach for 32 years, including 17 years running the men’s program at USC. Nothing irked him more than feeling like his team was robbed in a match.

“I will say that people in this event two years ago wanted to get physical,” says Smith. “They were so upset and so frustrated at line calls, they wanted to take it off the court. Which is unacceptable. I haven’t seen anybody complaining about a line call. Matter of fact, I’ve seen the opposite; somebody has been corrected by SwingVision, and they’ve apologized. Over and over.”

The threat of being overruled put players on their best behavior. Because their calls could be scrutinized, they tried harder to get them right in the first place. Instead of anything close to the lines being out, players were more generous with their judgment.

As good as the system proved to be, SwingVision still sees room for growth. It’s not difficult to operate, but you do need staff to maintain it during play. It also requires dependable wifi and extra batteries at the ready for matches that run long. The single camera system has limitations and there are instances when it can’t make the call. The next step is to expand the testing into the USTA Florida section, with an eye toward potential use at professional Challenger level events.

“Next year we’re looking for certification with the ITF,” says Swupnil Sahai, SwingVision’s co-founder and CEO. “The long-term vision is to be like Hawk-Eye Live where the calls are made right away.”

The USTA is concurrently trying out—and has also invested in—the Play/Replay ELC system at various junior events. There are plans to use it at several college events next season as well. The early feedback has been overwhelmingly positive, but it’s a much more elaborate and expensive option, requiring numerous cameras costing thousands of dollars. Given that SwingVision doesn’t have to be permanently fixed to the court and is remarkably inexpensive—adding roughly $10 per match—it presents a very attractive alternative.

“Our goals are to increase participation in our sport, and to provide a fun and fair landscape for tennis,” says Goldberg. “I’m not looking for perfection. I’m looking for improvement.”

Hard to argue with that call.