The Disappearing Line Judge and the Rise of AI

A couple of weeks ago, I attended the Hamburg Tennis Open (Hamburg Open ATP 500) in Hamburg, Germany. It was a very enjoyable day—the weather was outstanding, and the tennis was exciting. We (my son and I) sat very close to the clay court and could almost hear the players breathing.

In addition to the beautiful stadium location, the vibrant atmosphere, and of course the great tennis, something else caught my attention: there were no line judges at all. There was the umpire—and the rest was handled entirely by technology.

The calls – “Fault!” for a bad serve or “Out!” for a ball outside the court boundaries—were not the voices of experienced officials with sharp eyes, but synthetic sounds mimicking humans so well that it was hard not to look around for who was shouting. We could see cameras positioned around the court, and that was it. From time to time, when there was a very close call, a video clip would be displayed, convincing the players and the public that the call was accurate. I found it remarkable that, after seeing the video—which came from the same system that made the original call—no one argued.

The ritual of the umpire stepping down from their high chair and trotting to inspect the mark on the clay had vanished.

Throughout the day, I kept thinking that what I was seeing was a clear example of the AI revolution. Here we have a disappearing job, eliminated by advanced video technology, synthetic audio, fast computing, and intelligent algorithms. The result: a highly reliable automated line-calling system. Dozens of human line judges are no longer needed, and many people have lost a source of income.

Of course, it’s not easy to accept that human beings are no longer needed for a task. I didn’t have to wait long to see a contrast. This week, I’ve been watching the famous French Open at Roland Garros. I was surprised to see that line judges are still present and the umpire still steps down to inspect the mark left by the ball. I wondered—don’t the French have the technology?

It turns out that the French Tennis Federation has chosen to retain “this style of refereeing,” meaning dozens of professional, highly trained line officials are still at work—for now. One wonders about the reasoning behind this decision: is it merely tradition? It’s easy to predict that it won’t take many more French Opens before they, too, adopt the new technology.

This brings to mind other areas of life. In schools and universities, students are increasingly using ChatGPT and other AI applications to do their homework and projects. Software professionals are relying on AI to accelerate their work. Large companies such as Google and Microsoft report that 20%–30% of their code is now generated by AI. This shift comes with risks and challenges to human literacy and numeracy (the ability to understand and work with numbers—see here).

The tennis example offers us a lesson in technology adoption. In many cases, it carries a human cost that is hard to accept, and resistance is understandable. But the ongoing AI revolution is much more than this. It’s not just the line judges who risk being replaced—it’s the very capabilities of the players.