 Gamma responded by changing the length of the grip portion of the racket, to continue sales.The length restriction was based on the concern that such long rackets would make the serve too dominant, but that concern has never been objectively supported with testing.Moreover, some players, such as John Isner, are much taller and have longer arms than average professionals (and especially low stature ones), giving them a much larger advantage in terms of height for the service than is possible with several inches of racket length.