Comparisons between eras are difficult to make but encounters like the 1990 US Open semi final between Sampras and McEnroe give us at least some idea of how these matches would have played out. What stood out the most in this match was how much more powerful Sampras was. He was a better athlete, had better technique and was more comfortable from the baseline than McEnroe. Tennis was evolving from the artistry of McEnroe to the power of Sampras.
You don’t have to watch much of that video to notice that these points look very different to the gruelling baseline rallies which we have become accustomed to - and that’s not by accident. As Sampras serve and volleyed his way to 14 slams, which at the time was the most of any player ever, fans felt bored. The combination of racket technology improving, better technique and more physical training had meant serves had gotten out of hand. The ITF decided that in order to make tennis more entertaining to watch that they needed to slow the game down slightly.
As the ITF reworked its guidelines for ball manufactures and court specifications, they also explored other options to reduce the effectiveness of the new generation of power players. At Loughborough university in 2006, a study was conducted into the effects of increasing the size of the ball by 6%. The additional air resistance slowed the ball down more as it travelled through the air and the larger surface area made the ball bounce steeper, again giving the receiving player more time. Technical tweaks made sure that the bigger ball weighed the same as a regular sized ball, which was important as tennis elbow fears were a concern, however players reported they felt like the ball was heavier. This was a concern for the testers as that feeling encouraged players to try to hit the ball harder.
The study found that the bigger ball gave professional players 10% more time on average to react to the shot and for lower level players about 20% more time. The research also found that the average rally length went up by 25%. Of the 8 players involved in the study 6 preferred the bigger ball, 1 player had no strong feelings and the remaining player had a strong disliking of the ball.
It was even tested out in professional play during some fourth tier Davis Cup matches. The feedback from these matches wasn’t so positive though. I would say it’s likely that high level players have games based around attacking tennis including big serves and forehands and that these changes wouldn’t suit that style. For professional play I can imagine the rallies becoming ridiculous - hitting a winner past Djokovic already looks hard enough let alone if he has roughly 10% more time.
Whilst these balls never made it into high level professional play, the changes made to court and ball speed did and they continue to be massive talking points amongst those who are really invested in the sport. This is largely because the speed of the court has such an enormous impact on the tennis, both in terms of who's likely to win and also the enjoyment for the spectators. The change of court speed has also made it way more possible for players to be effective on both grass and clay courts. As clay courts have been sped up and grass courts slowed down the difference these days is far less than it used to be, making it far more possible to win the French Open and Wimbledon.
My take is that the idea that long rallies alone are entertaining isn’t entirely right. The speed and dynamism of the players to rally at such high speeds is what makes tennis great to watch. Slowing this down removes what makes it so impressive. It would be like watching shot put, everyone knows they couldn’t throw the ball as far as the guy on TV but it still looks remarkably underwhelming.
At one point these larger balls were commercially available. Despite the optimism from the the ITF and the people behind the project it seems the idea has now been buried in time, which in this case I don’t think is necessarily a bad thing.