Speed and Spin on Monte Carlo Clay

[jimlosaltos]

I'm keeping an eye on the sporadically published speed and spin data from the ATP, in part to check on consistency with the articles TPN published on new levels of velocity on tour, based on data from Roland Garros. Here are links to TPN's two articles.

https://www.tennisplayer.net/members...op_ball_speed/
https://www.tennisplayer.net/members...rn_heavy_ball/


Recapping: If the InfoSys data set, generated from HawkEye readings during Roland Garros is correct, several ATP players are regularly reaching velocities on their groundstrokes that had not been previously reported. Peak spins have NOT gone up, but per this data far more players are hitting at Rafa / Bruguera levels. Some raise questions about whether HawkEye is accurate at the highest levels. There is no third party confirmation of HE data that I'm aware of. However, MLB, which has the budget for and appears to do a lot more research than the ATP, is all in on StatCast, a more elaborate version of HawkEye. MLB regularly reports peak velocities such as "exit velocity" of home runs, and peak velocity for pitches, and even peak running speed of every player on the field. So, that's one vote of confidence.

However, even if the InfoSys peak speeds are off by 5% (which would be a lot more than radar variations and would seem inconsistent with claimed accuracy with ball location), the speeds would still be substantially above prior reports.
.
See Link: Ohtani obliterates a ball (119.1 mph!) for the hardest hit of his career
https://www.mlb.com/news/shohei-ohta...-hit-of-career

So far, the data is, at least, internally consistent. The ATP data lacks some specifics that Roland Garros' reporting had, but the top line numbers hold up.

Rallies on the much slower Monte Carlo (real) clay were at lower speed as players manipulated the ball around more. But the peak numbers were consistent, as are those from three other tournaments I've checked on different surfaces.

Look at some samples pulled from the ATP web site.

Here's a winner from Fokina during the final measured at 217 Km/H. The Spaniard was, in general, hitting with more pace more often than Tsitsipas.

filedata/fetch?id=97133&d=1650313599&type=thumb

This is a serve from Tsitisipas, an ace in the final, I pulled just to check for consistency in measurements. This clocks at 207 Kmh, or ~134 MPH, which is what Stef's flatter serves measure at frequently.

filedata/fetch?id=97134&d=1650313599&type=thumb

Here is a "winner" groundstroke by Tsitsipas shown at the identical velocity of 207 Km/H as well as 3,203 RPMs. Big and heavy.

Unlike Roland Garros' data set, the ATP data does NOT include the type of shot. It provides velocity for "Winners". I'm careful to look at the "height", which here is 3.6 feet, to not confuse an overhead for a forehand, and the court location. I also omit stats for a shot when one of the variables, often spin, is not reported, just to be safe.

filedata/fetch?id=97135&d=1650313599&type=thumb

While Zverev did not get as many of his big shots in court as he did at the French, I did find one presumed groundstroke that is up with his best numbers from the French stats -- 218 Km/H {or 135.5 MPH and 3,222 RPMs). I'll guess this was an inside-in forehand BUT Zverev is the only player I recall to reach 130 MPH on BOTH sides, forehand and backhand, in the French numbers.

filedata/fetch?id=97136&d=1650313599&type=thumb

[stroke]

TennisTV has not been supplying spin rate numbers, but they did on one forehand by Musetti that I saw at 4200+.

[jimlosaltos]

TennisTV has not been supplying spin rate numbers, but they did on one forehand by Musetti that I saw at 4200+.

4200 RPMs?

Wow. Love Musetti's stylish game -- although he seems to have gotten stuck, seems perhaps uncertain what to do when?

I suspect opponents hate it when he pulls the drop shot, volley-lob on them <g>.

[stotty]

It seems outrageous that a player can hit a ground shot at 135mph. I would question to accuracy of such a reading. I was at Wimbledon in person when Del Potro hit a forehand at 105mph which was awfully quick and struck by a bloody strong bloke. I thought then this must be about as hard as a ball can be hit off the ground.

[jimlosaltos]

It seems outrageous that a player can hit a ground shot at 135mph. I would question to accuracy of such a reading. I was at Wimbledon in person when Del Potro hit a forehand at 105mph which was awfully quick and struck by a bloody strong bloke. I thought then this must be about as hard as a ball can be hit off the ground.

Merits checking and skepticism, absolutely. Lack of third-party validation for HawkEye is a glaring hole.

But for context, in Ye Olden Days of radar, James Blake had a forehand measured at 125 MPH. Back then, most weren't even measured, so that comes from a small sample.

Others from "antiquity": Gael Monfils at 120MPH, Jock Sock at 120MPH, Juan Martine del Potro also at 120MPH, and Fernando Gonzalez at 117 mph.

Again, the tennis community accepts HawkEye service speed measurements as gospel. If HawkEye measures a serve at a given velocity and then a forehand by the same player in the same match at the identical velocity, why would only one of those be wrong?

[stotty]

Merits checking and skepticism, absolutely. Lack of third-party validation for HawkEye is a glaring hole.

But for context, in Ye Olden Days of radar, James Blake had a forehand measured at 125 MPH. Back then, most weren't even measured, so that comes from a small sample.

Others from "antiquity": Gael Monfils at 120MPH, Jock Sock at 120MPH, Juan Martine del Potro also at 120MPH, and Fernando Gonzalez at 117 mph.

Again, the tennis community accepts HawkEye service speed measurements as gospel. If HawkEye measures a serve at a given velocity and then a forehand by the same player in the same match at the identical velocity, why would only one of those be wrong?

I having never trusted it because I have sat there at Wimbledon and seen serves fast serves clocked slower than slower serves, and vice versa. True, that is my personal perception only but then what's wrong with seeing with one's own eyes. I'm not the only one. Many who have watched live tennis say they have witnessed the same.

I get the consistency argument but the consistency argument also covers up couple glaring errors in speed detection here and there.

Not sure if I could hit a 135 forehand even when hitting a ball into an open field for my dog to run and get.

[jimlosaltos]

I having never trusted it because I have sat there at Wimbledon and seen serves fast serves clocked slower than slower serves, and vice versa. True, that is my personal perception only but then what's wrong with seeing with one's own eyes. I'm not the only one. Many who have watched live tennis say they have witnessed the same.

I get the consistency argument but the consistency argument also covers up couple glaring errors in speed detection here and there.

Not sure if I could hit a 135 forehand even when hitting a ball into an open field for my dog to run and get.

I never miss an opportunity to use this Groucho Marx line:

"Who are you going to trust? Me or your lying' eyes?"

[jimlosaltos]

At the risk of overthinking things to the point of tedium: There is actually a reason a ball can correctly be perceived slower although measured faster by radar (other than misperception due to sound influence, etc).

Radar and presumably HawkEye measures the maximum velocity which is, as close as possible, to the "exit velocity" an instant after leaving the strings.

A ball with a great deal of spin, might have a higher exit velocity, yet slow down much more quickly, in actual velocity while also traveling a more curved path that takes more time to traverse.

So, it would be logical and correct for an observer to say, "That serve was slower", meaning overall it traveled slower from point A to B, while the radar/ HawkEye could also correctly say it was faster. The two are measuring different things.

Sorry. My long-dormant engineering education causes me to be pedantic and boring. .

At least, since I have never seen a woman post on TPN ( sadly) that I know of anyway, given aliases, I won't be accused of the dreaded Woke micro aggression "Mansplaining". Gasp !!!!