Originally Posted by Calor1
It's like being worse at your job, working less but getting paid just as much. I'd like to be a female tennis player to, best job in the world!
On topic: Is it only at the US Open that the balls differ? Or is it at the other majors too?
On the Wilson site there is only 1 version of the Wilson AO tennis ball (however it is available in either a 3-ball can or a 4-ball can). OTOH, aside from the 3-ball and 4-ball options, there are at least 5 versions of the US Open tennis ball: regular duty, extra duty, high altitude (extra duty)
, optic yellow grass court (reg duty)
, and white grasscourt (reg duty)
Does anyone have evidence that there is more than 1 version of the AO ball? I only see one version currently available for the the Wimbledon ball from the Slazenger site. Not looked at the balls currently used for RG (FO), but I believe that they often use a regular duty ball for many clay tournaments (for both men and women?).
Head/Penn balls are used for many ATP and WTA tournaments. The ATP often uses the Head ATP or Penn ATP ball (the same ball as the Head ball). The WTA often uses the Regular Duty (red label) version of the Penn Championship ball (and probably the Head Championship ball outside of the US).
the regular duty balls are any lighter that the extra duty ball is slight since all pro balls must follow the strict ITF guidelines. All balls, including high-altitude and slow (oversize/Type 3) balls, must fall in a fairly narrow weight range: 1.975
With the Penn Championship balls, the red label (regular duty) balls, to me, seems to be a bit softer than the extra duty balls (but I could be wrong about that). This could mean the the rubber is not as stiff and/or the internal pressure is slightly less for the regular duty balls.
Regular duty balls appear to be very slightly smaller in diameter due to the reduced felt content. Again, the size range is also confined to a fairly narrow range (see link above). The reduced felt probably causes the ball to encounter less air drag and, therefore, will slow down at a slower rate than extra duty ball. IOW, the regular duty is probably a bit faster than extra duty when flying thru the air. Don't know if the speed change due to the bounce is any different due to differences in the felt -- but the bounce speed change could be different if the rubber composition or internal pressure are different.