What happens inside a tennis player’s brain as they try to return a 148mph serve?

The fastest serve so far at this year’s Wimbledon tennis championships was struck by the Argentinian Thiago Agustín Tirante on the opening day.

His serve of almost 148mph (238km/h) was still some way under the Wimbledon record of 153mph, set by Frenchman Giovanni Mpetshi Perricard in 2025. And despite Tirante giving his opponent less than a fifth of a second to play each serve, he lost the match in straight sets.

Which means his rocket serves were successfully returned on lots of points. Our emerging understanding of how the human brain works can help explain how this feat is achieved.

Whether you’re a player or a spectator, the ability to see a tennis ball travelling that quickly across the court is a marvel of human physiology. At nearly 150mph, the ball is travelling faster than anyone can watch it move.

By the time your brain has processed the sight of the ball leaving the racket, it is already well on its way to the other end of the court. Yet professional tennis players return these high-powered serves with astonishing accuracy.

The reason is that they do not rely on reaction alone. Returning a tennis serve depends on one of the brain’s most remarkable abilities: predicting the future.

Predicting the future

Tennis players – and spectators – face the same basic problem: the visual information arrives in their brain slightly late.

Before a player becomes aware of a tennis ball hurtling across the court, light reflected from its surface has to be detected by their eyes’ retinas, converted into electrical signals, then transmitted along the optic nerves to the brain. There, the visual cortex begins analysing its colour, shape, speed and direction.

Even under ideal conditions, this takes around a tenth of a second. During that time, a ball travelling at nearly 148mph will have covered several metres.

For a spectator, this delay is rarely noticeable. The brain’s predictions are so accurate that the ball appears to move smoothly across the court, despite what you are seeing being a fraction of a second out of date.

But the player standing at the other end of the court needs to do a lot more than just watch the ball. They must move their body to that specific point on the court, position their racket and time their swing with great precision if they want to be in with a chance of winning the point.

In fact, much of this process begins before the ball has even left the opponent’s racket. It is an extraordinarily complex system.

How the brain works it all out

As the server prepares to strike the tennis ball, the receiver is already gathering information. The height and position of the ball toss, the rotation of the server’s trunk, the movement of their shoulder and forearm, the angle of the racket face and the speed of the swing all provide clues about what is about to happen.

Elite players have, of course, spent many thousands of hours learning to recognise these subtle biomechanical cues. Their brains combine the latest cues with all that previous experience to estimate the likely speed, direction and spin of the serve – before the ball has even crossed the net.

Central to this is the cerebellum, a densely folded structure tucked beneath the back of the brain. Although best known for coordinating movement and balance, advances in brain imaging and computational neuroscience have revealed it is also one of the brain’s great prediction engines.

Rather than simply responding to sensory information as it arrives, the cerebellum continuously generates internal models of how the body and external world behave. As fresh visual information reaches the brain, these models are updated almost instantaneously, allowing movements to be adjusted before conscious awareness has caught up.

But the cerebellum does not work alone. A specialised region of the visual cortex, known as area MT or V5, is exquisitely sensitive to movement, and calculates the speed and direction of the ball as it crosses the player’s visual field.

This information travels along the dorsal visual stream – often called the brain’s “where pathway” – to the posterior parietal cortex, where the ball’s position is integrated with information about the player’s own body.

The brain’s two visual streams

From there, premotor regions begin preparing possible movements. The supplementary motor area helps organise their sequence, and the primary motor cortex sends commands to the muscles of the trunk, shoulder, arm and wrist.

At the same time, the frontal eye fields and the superior colliculus (a small structure in the midbrain that rapidly redirects the eyes towards objects of interest) generate rapid eye movements towards where the ball is expected to be next – rather than where it was a fraction of a second ago.

This is why the fastest returns in tennis are not simply feats of lightning-fast reflexes. They are the product of a brain that is constantly making, testing and refining predictions. The players who appear to have more time have become exceptionally good at anticipating what will happen next.

Tennis and beyond

Neuroscientists are still trying to understand why some tennis players acquire these remarkable predictive skills faster than others. Is it simply a matter of hours spent on court, or are some brains naturally better equipped to build the internal models that underpin elite performance?

For now, the answer appears to be a combination of both.

Understanding how the brain predicts movement has implications far beyond tennis. Similar neural mechanisms help us catch a falling glass before it hits the floor, judge when it is safe to cross a busy road, or drive through traffic.

These predictive systems are becoming an important focus of neuroscience research. Insights into how the cerebellum and wider motor networks anticipate movement are helping researchers improve rehabilitation after neurological injury, understand disorders of movement and coordination, and design robots capable of interacting more naturally with an unpredictable world.

Meanwhile, insights from neuroscience might also help hone a future Wimbledon tennis champion.