Tennis Industry magazine


What’s Fair is Fair

A tennis aficionado has suggestions to make the Hawk-Eye Officiating System better for everyone.

By Greg Raven

Whether it is a let-cord monitor, a “Cyclops” service-line monitor, or the Hawk-Eye Officiating System, electronic enhancements to human officiating have become part of the game.

Anyone who doubts the purchase that these technologies have gained in the world of tennis has merely to watch a replay of Andy Roddick’s Davis Cup match against Joachim Johannson in Sweden from this past September. Despite the fact that no instant-replay challenge system was available to players, Roddick barely seemed able to stop himself from signaling for electronic review of a couple of close points.

This is not the same as saying that these technological wonders are universally adored, or even accepted. At one time or another, players over the years have asked that the let-cord monitor or Cyclops be turned off.

With Hawk-Eye, the system is so advanced it’s possible that no player really understands how it works. And even though the International Tennis Federation accepted the Hawk-Eye Officiating System in late 2005 after extensive tests (the system was first employed at the 2006 Nasdaq-100 tournament in Miami), players have expressed serious doubts about it. World No. 1 Roger Federer asked that it be turned off during the 2007 Wimbledon final, and world No. 2 Rafael Nadal was highly critical of Hawk-Eye at the 2007 Dubai Tennis Championships.

Even fans have to wonder about the accuracy of a system that isn’t used at Roland Garros, where Hawk-Eye reports would be subject to direct comparison against the actual mark on the red clay. Stephane Simian, sports director of the French Tennis Federation, told Tennis Week in 2005 that in tests, Hawk-Eye’s results were off by as much as 10 mm (.4 inches). Given that the felt on the outside of a tennis ball can easily add 5 mm to the diameter as it fluffs up, this seems reasonably accurate, and the system may now be even better than it was two years ago.

The rub is that on some extremely close replays, Hawk-Eye operators sometimes have to zoom in on the computer-generated ball mark to see if the call should be “in” or “out.” In cases where the ball is out by the slimmest of margins, there is no caveat about errors in the system that may be enough that the call could go either way. In other words, Hawk-Eye results are presented as being hyper-accurate, its actual accuracy notwithstanding.

As many commentators have pointed out, even if Hawk-Eye were perfect, the implementation leaves something to be desired. At pro matches from the Futures level on up, officials are in place to call the lines. Why, with a tool as powerful as Hawk-Eye, are we now saying to the players, in effect, “We know exactly where the ball landed, but unless you ask us the right way at the right time, we’re not going to tell you what we know”?

Given that the game seems to be getting faster each year, something needs to be done to help both players and officials. Human cognizance has built-in limitations; it’s simply not possible for the unaided eye to see exactly where the ball is for the .004 seconds it’s in contact with the court surface.

Instead, the brain calculates the point of impact based on the incoming ball trajectory and the resulting bounce off the court. If you are seeking certainty in line calling, then some sort of computer aid is needed. Even deciding that Hawk-Eye is the answer doesn’t solve the problem, though. Because of the expense of installing the system, it isn’t used on every court even at large events.

As I see it, Hawk-Eye has two main strengths: First, it is a good system, and it’s undoubtedly getting better. Second, it’s so technical and complex that most people would rather simply assume that it must be accurate. Why not leverage that grudging acceptance, put a human face on the technology, and improve officiating across the board? Here’s what I have in mind:

Every linesman should be equipped with a device that gets a direct feed from Hawk-Eye, so that every human line call is backed up by its technological counterpart. “In” balls could be signaled through an earphone by a Pong-like “boop,” “out” balls could be signaled by a “blat,” and “unsighted” balls would have no associated sound. Instead of leaving human line calls to the mercy of Hawk-Eye, linesmen and Hawk-Eye would work in cooperation. And with Hawk-Eye involved on every call, we could do away with the cumbersome and unfair challenge system.

Just as important, this immediate feedback would help linesmen improve their already-good skills. As Hawk-Eye-assisted linesmen rotated out to courts that lack Hawk-Eye technology, they’d take their training with them, improving calls on every court at every tournament.

That way, the technology could be used to help everyone. Even players. Maybe a set-up such as this could even help improve Hawk-Eye itself.

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About the Author

Greg Raven  is an associate editor for Tennis Industry magazine and technical writer. He is certified as a Master Racquet Technician by the U.S. Racquet Stringers Association. He can be reached via e-mail at, or through Facebook, LinkedIn, and Twitter. He plays tennis three to five days a week, and is turning into an avid cyclist.



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