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Jim, great stuff. No doubt to my eye these young guys like Rune, Tsitsipas, Korda are producing some groundstrokes, speed and spin totality, on a new level. I am sure you have seen this occasional TennisTV stat where they, during a set, will give their "quantitative " measure of each players forehand "heaviness". That spin/speed thing must be the measure of such a result.
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Last edited by stroke; 01-27-2023, 12:52 PM. -
Amazing post....Originally posted by jimlosaltos View PostSpeeds of Serves & Groundstrokes at Australian Open 2023
I continue to track speed & spin of ATP players' since the pair of articles for TPN I collaborated with John on, based initially on a new level of detail released during the French Open.
Ball speed article: https://www.tennisplayer.net/members...op_ball_speed/
Some of John's earlier work on Sampras et al
https://www.tennisplayer.net/members...nis_page1.html
Here are two examples of shots by Holger Rune when playing Andrey Rublev during this fortnight's Australian Open, a serve & a forehand at identical speeds of 121 MPHs. I have laboriously extracted this information, which requires searching and clicking on individual shots, and gotten 120 MPH+ groundstroke data for Tsitsipas, Rune, Medvedev, Djokovic, Korda, and Rublev.
First, we have an ace by the 19 yo Dane. Loads of stats a flat serve, at 121 MPH, was 3.9 feet above the ground (presumably when it crossed the net? not specified), and bounced 4.6 feet high. Good, ATP level serve, nothing spectacualr
filedata/fetch?id=99556&d=1674848192&type=thumb
Next, we have another winner by Rune, a forehand at an identical 121 MPH, landing almost on the sideline, with 2,485 RPM, and 5.2 feet above the ground (again, not specified where).
This is one huge forehand. Up until a few years ago, a 120+ MPH forehand would be newsworthy. There would be videos on YouTube, including with fastest ever shots by the likes of Fernando Gonzalez and James Blake. Now, at least per the stats I've found at Roland Garros and replicated at other events from San Diego to Indian Wells, most of the top 10 players and many other regularly reach 120 MPHs.
The fastest groundstrokes combined off both sides at Roland Garros, came from Sasha Zverev, who reached 130 MPH with both forehands and backhands -- per the HE/RG stats.
There are reasonable doubts. First, it sounds huge. Second, we're trained to expect serves to be faster than groundstrokes. Part of that may be that we are traditionally given "average" speeds for groundstrokes and individual speeds for serves. The variation in groundstroke speed is much greater than that for serves (Other than, say, an underhand serve by Kyrgios, one seldom sees a 40 mph serve). Finally, John got feedback off the record from a USTS official that that although they believe in HawkEye's accuracy in calling lines, they think the top speeds are off. No specifics were given.
Now, I don't have a dog in this fight. I'd just like to know. My skepticism of the skepticism is this; If we believe, as almost everyone seems to accept, that HawkEye is extremely accurate at measuring service speeds, why would it be inaccurate measuring an identical speed on a shot hit seconds later on the side instead of above the head?
Secondly, although we have ZERO independent verification and test results on HawkEye that I'm aware of (a glaring omission IMHO), a more sophisticated, more complicated HawkEye system is used by Major League Baseball to provide stats on every game in every stadium. MLB publishes detail down to fractions of a MPH, "launch angles" of home runs, and reaction time of players. MLB is a much larger business with far more resources invested in this & I presume doesn't want to risk its reputation heavily promoting inaccurate numbers.
Finally, I can understand how HawkEye could measure speed and spin impeccably but get the spot wrong, since its version of a "ball mark" is actually a computer simulation. But I can't understand how HawkEye could simulate the landing of the ball (remember, unlike FoxTen HE has no cameras at ball level), if the stats it would be calculated on are wrong. Garbage In = Garbage Out.
Perhaps that is my lack of imagination.
More to come in the future, presumably.
Seems outrageous that forehands are reaching such high speeds. A while back I read Wawrinka was the biggest hitter on tour off both wings, averaging the low 80s mph on his forehand and backhand. Del Potro was once singled out at Wimbledon for hitting a 104 mph forehand, which was thought to be the fastest ever hit at SW19.StottyComment
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I don't doubt those are the posted stats. Just not sure I believe them. As I posted before a USTA insider tells me that on the groundstrokes any data above 100mph is "unreliable" what ever that means...Comment
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Yup, John, I believe I referred to that USTA off the record comment.Originally posted by johnyandell View Post
I understand your skepticism. I waiver between that and acceptance because the alternative is so bizarre.
As I said, I don't have a dog in this hunt. But until proven otherwise, this is what the professional tennis industry is reporting.
Sorry to be verbose but ...
If the "old" speeds are both correct and what players are still achieving, then the errors are about 20-30% or more. A 10% error would be astonishingly incompetent.
Can they provide ANY explanation for why HawkEye can measure the speed of a serve with great accuracy, but not only can not measure a slower groundstroke accurately but has extremely large errors?
And, if that is correct, and the USTA knows this, why have the ATP, French Tennis Federation, and Tennis Australia been posting those numbers for a couple of years now? If its groundstroke numbers are inaccurate -- and we're not talking small errors, but very large ones -- how can they claim electronic line calling is as close to infallible as they want people to believe it is? HawkEye doesn't take a picture of the impact, it computes it from speed, direction and spin. If one of those is way off, the calculation is off.
Hand held radar guns at $300 claim accuracy of +/- 1% or 3 mph up to 130 mph on a baseball {although user reviews vary} $3,000-$5,000 units better
But a $60,000 HawkEye system {not incl cost of staff to run it}, calibrated for a given stadium, can't do as well?
Major League Baseball seems to claim an accuracy of fractions of a percent for its HawkEye system {although I haven't found a specific "guarantee"}, but that is more complex with, I believe it is currently 12 cameras per stadium covering a much larger area.
That would seem to imply that HawkEye, as implemented in tennis, is just plain broken. Which would be a story in itself.
Oh, well back to watching matches
Last edited by jimlosaltos; 01-27-2023, 05:23 PM.Comment
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Yeah. From memory, the fastest speeds recorded using old radar technology were 125 MPH for James Blake and shots by both Delpo and Fernando Gonzalez at around 120 mph. There are YouTube videos for whatever it is worth to simply look at them.Originally posted by stotty View Post
Amazing post....
Seems outrageous that forehands are reaching such high speeds. A while back I read Wawrinka was the biggest hitter on tour off both wings, averaging the low 80s mph on his forehand and backhand. Del Potro was once singled out at Wimbledon for hitting a 104 mph forehand, which was thought to be the fastest ever hit at SW19.
I wonder if there is any reason a forehand, striking an incoming ball going, say 50 mph, wouldn't generate more speed than hitting a stationary service toss?
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Yes, I have mixed feelings about their "synthetic" stats. I wish they told us what went into them. But they probably feel that would alienate the less involved viewers.Originally posted by stroke View PostComment
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“Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns- the ones we don't know we don't know.”Comment
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Happy to see Sabalenka win her first major. After her "painful to watch" struggles with her serve, it was nice to see her come up "big" with it in pressure moments. Was it ever determined which biomechanist she was working with?
SeanOComment
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Novak on a mission. Tstsipas will need help from up above to pull this one off.Originally posted by stroke View PostComment
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This is a very good article on the mens semis. It gets into some interesting technique stuff on Tsitsipas' backhand, both the topspin and slice. I have often wondered exactly why his slice backhand is clearly not nearly as good as Roger's or Grigor's, or even Gasquet's or Evans. I think the author of this piece is on to somethingComment
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Individual rights vs. public good. Always a tough debate. Novak stood up for individual rights. He bided his time and now he is back. Of course, he was willing to take as many COVID tests as needed.Originally posted by don_budge View Post2023 Australian Open...Novax appears to be the winner according to Scott Adams (not referring to tennis)
Scott Adams makes a rather bizarre video regarding the COVID Vaccines. Novak Djokovic took a stand and refused to take the jab. But it cost him a shot at winning his 10th Australian Open Championship. A rather steep price considering. The forum ganged up on him last year. He had the audacity to think for himself. I read it. I didn't participate...being on sabbatical as I was.
https://www.youtube.com/watch?v=C41GCgyG4mI&t=182s
I completely disagree with him. I had childhood Asthma and ended up in the hospital for an overnight stay when I was 3 and a half. I would take ANY jab to avoid feeling like I was losing my breath. It is the most horrible feeling in the world. There is no painfree euphoria when one is unable to breathe.
Novak clearly had a different life experience. As long as he is making sure not to infect others, I am okay with it.
The problem is he was putting others at risk. Having tournaments and infecting lots of people. He felt he was above others and the illness. If he had really known what it was like to be out of breath, I am sure that he would think differently.
As I said, individual rights vs. public good. Always a tough debate.
All I can say is that 5 shots and one COVID infection later, I am glad to be on the other side of this whole thing. I really appreciate seeing others these days.
Hope all of you are healthy and enjoying the company of others!Comment
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Well put. Djokovic learned nothing from the disastrous Adria Tour.Originally posted by arturohernandez View Post
I'd add that it is a big leap from making an individual choice to not get vaccinated to openly promoting pseudo-science above modern healthcare, as Djokovic did when he promoted a scam artist's fake alien pyramids and the healing power of their tunnels. People are paying to visit this hoax because of his celebrity.Comment
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Agreed. Saby's success is an interesting lesson for all of us about dealing with the "yips". There's a line of thought that once one has them, it's too psychological to overcome. Clearly, she did. Going from hitting 50+ double faults in a match to a major title, where she served with as much pressure as you can face in her profession. Kudos.Originally posted by seano View PostComment
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To me, we are all responsible for our own decisions. If someone decides to go for some pseudo science whatever because Novak promoted it, that is completely on them to me.Originally posted by jimlosaltos View PostComment
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