The world table tennis ruling body has been changing rules in order to make the game a greater spectacle, but inadvertently putting an early end to a few glorious careers including Liu Guoliang's.

The older 38mm (1.50 inch) balls were replaced by 40mm (1.57 inch) balls in October 2000. This increased the ball's air resistance and effectively slowed down the game.

By that time, players had begun increasing the thickness of the fast sponge layer on their paddles, which made the game excessively fast and difficult to watch on television.

A few months later the ITTF changed from a 21-point to an 11-point scoring system and the serve rotation was reduced from five points to two. This was intended to make games more fast-paced and exciting.

In 2002, the ITTF also changed the rules on service to prevent a player from hiding the ball during service to increase the average length of rallies and to reduce the server's advantage.

Liu Guoliang, now the Chinese national team head coach, had been struggling as a player since the 40mm ball was used and had to retire after his service advantage was taken away.

Gone with a great player, came a great coach, just like his mentor Cai Zhenhua.

Cai, now a Chinese vice sports minister, had to retire after his paddle covered by the same-color rubbers was banned in 1985.

The ongoing world championships uses a new plastic ball, a decision made by the ITTF in 2014.

The ITTF ruled that all international competitions will use the new ball, replacing the traditional celluloid material. The change was made in order that the ball be more visible to TV audiences and slow the pace of the game.

These changes combined have served to assure the future of table tennis into the modern era and make an exciting sport ever more dynamic and appealing.