<P> After the 2000 Olympics in Sydney , the ITTF instituted several rule changes that were aimed at making table tennis more viable as a televised spectator sport . First , the older 38 mm ( 1.50 in ) balls were officially replaced by 40 mm ( 1.57 in ) 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 ) , effective in September 2001 . This was intended to make games more fast - paced and exciting . The ITTF also changed the rules on service to prevent a player from hiding the ball during service , in order to increase the average length of rallies and to reduce the server 's advantage , effective in 2002 . For the opponent to have time to realize a serve is taking place , the ball must be tossed a minimum of 16 cm in the air . The ITTF states that all events after July 2014 are played with a new poly material ball . </P>
<P> After the 2000 Olympics in Sydney , the ITTF instituted several rule changes that were aimed at making table tennis more viable as a televised spectator sport . First , the older 38 mm ( 1.50 in ) balls were officially replaced by 40 mm ( 1.57 in ) 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 ) , effective in September 2001 . This was intended to make games more fast - paced and exciting . The ITTF also changed the rules on service to prevent a player from hiding the ball during service , in order to increase the average length of rallies and to reduce the server 's advantage , effective in 2002 . For the opponent to have time to realize a serve is taking place , the ball must be tossed a minimum of 16 cm in the air . The ITTF states that all events after July 2014 are played with a new poly material ball . </P>
when did table tennis change from 21 to 11
when did table tennis change from 21 to 11
September 2001
September 2001