For most of the sport's history the racket was a piece of bent and glued wood, and the tennis played with it looked nothing like the game on television today. The change from wood to modern composites took about twenty years and altered almost every tactical assumption the sport had.
A wooden racket was heavy, had a small head, and flexed. The sweet spot - the area of the string bed that returns the ball cleanly - was roughly the size of a hand. Miss it and the frame twisted, the shot died, and the vibration went straight up the arm. Everything about how players stood, swung and chose their shots followed from those facts.
What wood demanded
Because the sweet spot was small, players hit with long, smooth, repeatable swings and tried to meet the ball in exactly the same place every time. Because the frame was heavy, they generated pace by timing rather than by brute racket-head speed. Because mishits were so punishing, the percentage play was to keep the ball in front of you and come forward.
Rackets also had to be stored in wooden presses, clamped flat, or the frame would warp between matches. Players travelled with half a dozen of them and a screwdriver.
The steel experiment
The first serious challenge to wood was a steel frame with an open throat, lighter and more powerful than anything before it, which a handful of professionals adopted in the 1960s. It had a reputation for being unforgiving and for doing unpredictable things to the ball, and most players disliked it.
One did not. Jimmy Connors built an entire career on a steel racket, hitting flat and early off both wings, and his success made it very difficult for anyone to keep claiming that wood was simply better.
The oversized head
The genuinely disruptive idea arrived in the mid-1970s: make the head much bigger. An aluminium frame with an enlarged hitting area was marketed to club players as an easier racket, and it was. It was also, as professionals quickly worked out, a more powerful one, because a larger string bed means a larger sweet spot and more string movement behind the ball.
Governing bodies eventually set limits on how far this could go, capping the dimensions of a legal racket. Without those limits there is no obvious reason the head would have stopped growing.
Composites
Graphite and carbon-fibre composites arrived in the 1980s and settled the argument for good. A composite frame could be made stiff where stiffness helped and flexible where it did not, could be light and powerful at the same time, and did not warp, rot or need a press.
Within a decade wood had disappeared from professional tennis entirely. The last wooden rackets in major competition look, in retrospect, like something from a different sport.
A bigger head meant a bigger sweet spot. A bigger sweet spot meant players could swing harder at balls they used to have to respect.
The strings nobody noticed
The frame gets the credit, but the quieter revolution was in the strings. Natural gut was replaced at the top of the game by stiff polyester, which grips the ball and lets a player swing at full speed with an enormous amount of topspin and still find the court.
That single change is why the modern baseline game looks the way it does: heavy, looping groundstrokes struck from well behind the baseline, landing short of the line and kicking up above shoulder height. With gut strings in a wooden frame, that shot simply does not exist.
Professional players still have their rackets customised by hand, with lead tape added at specific points on the frame to adjust the balance and weight. Two rackets of the same model, from the same bag, are rarely identical.
What it did to tactics
Serve-and-volley tennis was the first casualty. Passing shots struck with heavy topspin dip sharply as they cross the net, which makes the first volley far harder and the net a far more dangerous place to stand. Within a generation the dominant style on every surface became powerful baseline play.
Returning also changed. A player can now take a huge swing at a fast serve and expect the ball to land in, because the frame does some of the work and the strings keep the ball down. The free point that a big server used to count on is much less free than it was.
Where it stops
Equipment regulation in tennis is deliberately conservative. The rules fix maximum dimensions and ban anything that changes the ball's behaviour by active means, which is why the racket of today looks broadly like the racket of twenty years ago. Improvement now happens in materials and in string technology rather than in shape.
It is worth remembering when watching old footage that the players were not worse. They were solving a different problem with a different tool, and many of the shots that look quaint were the correct answer to the equipment in their hands.
The club player's share of it
Almost every advance in racket design was sold to recreational players first and adopted by professionals afterwards, which is the reverse of how equipment usually travels in sport. The oversized head, the lighter frame and the stiffer composite were all marketed as help for people who miss the middle of the strings.
That matters because it explains the pace of change. Professional tennis is a small market; club tennis is an enormous one, and the money that funded the research came from people who simply wanted the ball to go over the net more often. The side effect was a professional game transformed within one generation.
