MEN’S TENNIS RESULTS FROM THE WINSTON-SALEM OPEN

Written by: Staff on 20th August 2014

ATP Tennis Tournament in Washington, DC.

MEN'S TENNIS RESULTS FROM THE WINSTON-SALEM OPEN

epa04339249 Donald Young of the United States returns a shot to Milos Raonic of Canada during their semifinal singles match at the Citi Open ATP tennis tournament in Washington, DC, USA, 02 August 2014. EPA/PETE MAROVICH |

* Donald Young saves 3 match points and then drops two match points against Garcia-Lopez . Very tough 3 set battle

* Lu “upsets” Granollers, Janowicz truly upsets Roger-Vasselin, Goffin eliminates Nieminen

* Querrey tops #2 seed Anderson

****** TODAY’S MEN’S NEWS ******

Winston-Salem

Singles – Third Round: (1) J Isner def. (13) M Kukushkin 6-1 7-6(7-3)

John Isner won’t move in the rankings this week, but at least he’s starting to add points. And, with the draw opening up, he has a very good chance of winning the tournament — and, hence, the U. S. Open series.

Singles – Third Round: S Querrey def. (2) (WC) K Anderson 7-6(7-4) 6-4

There was only one break in this match, but that was enough. It’s one of the best wins for Sam Querrey this year. Unfortunately, he made the semifinal last year, so he still needs another win just to maintain his #56 ranking. Kevin Anderson will keep the #20 ranking he came in with.

Singles – Third Round: (9) Y Lu def. (8) M Granollers 6-1 6-2

Although Marcel Granollers was seeded higher, he actually came here ranked behind Yen-Hsun Lu (#42 versus #38) — and it will stay that way; Granollers will not rise above his current ranking, and this win means that Lu will keep his Top Forty spot.

Singles – Third Round: (7) L Rosol def. (10) P Andujar 1-6 6-2 6-2

This took only an hour and 22 minutes, which shows you how lopsided the individual sets were. This isn’t enough to count for Lukas Rosol, but it means Pablo Andujar won’t rise above his current #47.

Singles – Third Round: (5) G Garcia-Lopez def. (11) D Young 6-7(4-7) 6-3 7-6(8-6)

After two and three-quarter hours, leading 6-5 in the tiebreak and serving, Donald Young double-faulted. Two points later, he was out of the tournament. Garcia-Lopez is one win away from the Top Thirty; Young loses his chance to rise above his current #46.

Singles – Third Round: J Janowicz def. (12) E Roger-Vasselin 4-6 6-3 6-4

It’s still too soon to say that Jerzy Janowicz will return to the Top Fifty, but he’s getting close.

Singles – Third Round: (14) A Seppi def. N Mahut 6-4 7-6(9-7)

Nicolas Mahut loses the chance to clinch a return to the Top Hundred, but at least he looked better than he has for several months. Andreas Seppi hasn’t earned any points yet, but any additional wins will count.

Singles – Third Round: (Q) D Goffin def. (15) J Nieminen 6-4 4-6 6-4

Even though David Goffin is a qualifier and Jarkko Nieminen is a seed, the rankings gap here was quite small — Goffin #62, Nieminen #54. Goffin just doesn’t seem to understand scheduling (or consistency). The loss means Nieminen will likely remain below #50; Goffin has a real chance to end up the higher-ranked of the two.

Doubles – Quarterfinal: Mergea/Sousa def. (WC) Monroe/Young 6-2 1-6 12-10

Just as Donald Young did in the singles, Monroe/Young had a match point on serve in the match tiebreak here. You can see the result. Donald Young will have a lot to think about overnight….

TODAY’S FEATURE This is For the truly hardcore. Or the math / stats peeps

Resistance Is Futile

At this time a year ago, Ryan Harrison was credited with a 152 mile per hour serve. Another source calculated it at 138 miles per hour. We calculated it as, frankly, not possible. Unless Harrison was firing from a pogo stick, he isn’t that tall. And what does the disagreement tell you? It tells you that the whole radar gun question (and the semi-related shot-placement technologies) are a lot more complicated that they seem. We thought we’d resurrect one of our old features on the topic.

A curiosities of tennis is that one of its most-touted statistics isn’t even an official statistic. We’re referring, of course, to serve speeds as measured by radar guns. Tournaments love to offer this statistic, and it’s even included in the ATP and WTA media guides — but it doesn’t matter if you can serve the ball 600 miles per hour; if the other guy wins enough points, you’re going to lose the match.

And there is another reason not to trust service speeds too much. The reason is that they aren’t actually measured. Radar guns approximate service speeds, and they approximate them differently.

Let’s explain. This is going to get pretty complex before we’re through; we’re going to do our best, but it isn’t easy. We’ll try to use graphs to help you out.

The real problem is that tennis balls slow down a lot. And the faster they’re moving, the faster they’re slowing down. There is a nice hairy formula measuring this, calculating the force pushing against an object moving through the air.

2 C A p v f = --------- a 2

Where fa is the force of air resistance, C is the drag coefficient, A is the cross-sectional area (in this case, of the ball), p (that’s actually a Greek rho, ρ) is the density of the air, and v is the velocity of the ball at the point we’re measuring. Which in turn means that the acceleration of the ball (from the above and Newton’s famous f=ma) is given by

2 C A p v a = --------- 2m

Note that A and m are constant for all tennis balls of a particular model (and almost the same for all tennis balls), and C and p will be effectively constant for any given match (barring an extreme weather change in mid-match). Which means, in a word, that for any given match, the rate at which the ball decelerates depends solely on how fast it’s moving — and the faster it’s moving, the more it slows down. And, because the velocity term is squared, that means that the ball slows down much, much more when it’s moving quickly than when it’s moving slowly. Hit a ball twice as hard and it will slow down four times as fast. Hit it three times as hard and it will slow down nine times as fast. The payoff for a few extra miles per hour on a serve is surprisingly small.

(This, incidentally, is why cars have poorer fuel efficiency when they are driven at high speeds. There are two forces which slow cars down once they’ve gotten moving: Road friction and air friction. Road friction is almost constant no matter how fast you drive — in fact, it decreases slightly at high speeds — but air friction increases according to that squaring rule. In a typical car, at speeds around 20 miles per hour/30 kilometers per hour, road friction is four times air friction. Get up to 60 mph/90 kph, and air friction is more than twice the road friction. It is, ironically, only the very inefficiency of automobile engines — which throw away two-thirds of the energy produced by the gasoline as heat — which makes high-speed cars economically viable; if engines were 100% efficient, a car driving 60 mph would get only a third the gas mileage of a car driving 20 mph, and we’d have everyone slowing down simply because driving fast costs so much!)

But if the ball is slowing down from the moment the serve is hit, just what are we measuring? It clearly isn’t the average speed of the ball — one of Ivo Karlovic’s balls, if it had an average velocity of 150 mph/240 kph, would be literally unreturnable; it would be in the stands on the far side of the court in half a second! No, the goal with radar guns, which are there mostly to supply inflated statistics, is to find the instantaneous velocity — how fast the ball is moving the moment it comes off the server’s racquet. This, we must note, is essentially impossible; we measure velocity by dividing distance covered by time. We have to project back from that to the initial velocity. And, for reasons which will eventually become apparent, we also want to find its velocity at every other point along its trajectory. This requires, formally, a bunch of calculus, integrating distance over time. We’ll spare you that, just constructing some numbers to cover the situation. We’ll start with a serve with an actual initial speed of 170 kilometers per hour (since that’s a speed that almost every man and very many women can hit, at least occasionally), which is the same as 47 meters per second. We assume the ball is hit from a moderate height. We assume a serve down the T. It turns out that it takes almost exactly 3/4 of a second for the ball to land, at point 18 meters from the point at which it’s hit.

We must note loudly that this is just a single “typical” serve; there are all sorts of variations on this theme, some faster, some slower. It may not even be a possible serve, at least for shorter players; we’re assuming they hit flat, and that may not be possible from some serving positions. We’re studying radar guns, not serves! But working out one serve based on the above data (starting speed of 170 kph, straight down the T, with an insignificant vertical component), we find the following “picture.” The table below shows the time in seconds, the approximate velocity of the ball at that time, and the distance travelled. We will examine things at .05 second intervals. Note that, at the beginning, the ball covers more than two meters in .05 seconds. By the end, it’s covering only a third of that distance in the same amount of time. The speed drops precipitously at the start (shedding almost a sixth of its velocity in that first twentieth of a second), much less at the end.

TIME….VELOCITY….DISTANCE

0.00……47.00…….0.00

0.05……39.93…… 2.23

0.10……34.83…… 4.14

0.15……30.95…… 5.82

0.20……27.88…… 7.32

0.25……25.39…… 8.67

0.30……23.33…… 9.90

0.35……21.59……11.04

0.40……20.10….. 12.10

0.45……18.81……13.08

0.50……17.67….. 14.00

0.55……16.67……14.87

0.60……15.78……15.69

0.65……14.99……16.46

0.70……14.27….. 17.20

0.75……13.62….. 17.90

Of course, if we want to make this clear, we need a graph. We’ll put time on the horizontal axis, distance covered on the vertical.

18 -|- : : : : : : : # D | : : : : : : : I 17 -|- : : : : : : # S | : : : : : : # : T 16 -|- - - - - - - - A | : : : : : # : N 15 -|- : : : : : # : : C | : : : : : : : E 14 -|- - - - - # - - | : : : : : : : 13 -|- : : : : # : : : | : : : : : : : 12 -|- - - - # - - - | : : : : : : : 11 -|- : : : # : : : : | : : : : : : : 10 -|- - - # - - - - | : : : : : : : 9 -|- : : # : : : : : | : : : : : : : 8 -|- - - - - - - - | : # : : : : : 7 -|- : : : : : : : | : : : : : : : 6 -|- - # - - - - - - | : : : : : : : 5 -|- : : : : : : : | : : : : : : : 4 -|- # - - - - - - | : : : : : : : 3 -|- : : : : : : : | : : : : : : : 2 -|- # - - - - - - - | : : : : : : : 1 -|- : : : : : : : | : : : : : : : 0 -#--|--|--|--|--|--|--|--|--|--|--|--|--|--|--| 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 TIME 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5

This isn’t a great graph, of course — the resolution is too coarse — but surely it’s obvious that the ball is just sort of sputtering to a halt.

Now let’s think about radar guns, and what they do. The basic technique is to measure the ball’s position twice, and then perform a very simple calculation: speed is equal to distance covered divided by time.

Now let’s create four different hypothetical radar guns, and look at what they produce.

Radar gun 1 takes two readings, at 0 seconds and .05 seconds.

Radar gun 2 takes two readings, at 0 and .1 seconds.

Radar gun 3 takes two readings, at .1 and .2 seconds.

Radar gun 4 takes two readings, at .2 and .4 seconds.

Are you ready for this? On the exact same serve,

* Radar gun 1 measures a speed of 44 meters per second, or 161 kilometers per hour, or exactly 100 miles per hour (pure coincidence; we did not plan that).

* Radar gun 2 measures a speed of 41 meters per second, or 149 kilometers per hour, or 93 miles per hour

* Radar gun 3 measures a speed of 32 meters per second, or 115 kilometers per hour, or 71 miles per hour

* Radar gun 4 measures a speed of 24 meters per second, or 86 kilometers per hour, or 53 miles per hour

Obviously the actual radar guns in use don’t vary as much as our four hypothetical radar guns. Our first gun was “fast” because it was, in fact, very “fast” (it measured the ball very early in flight, and made its two measurements very close together). Most actual radar guns have characteristics probably somewhere between gun 1 and gun 3. But they do differ slightly, meaning that two guns can and do and will produce different readings on the same serve.

You can, of course, get cleverer than this. All of our guns were dumb, taking just two data points. You can take more — for example, measure the speed at .05, .10, and .15, and construct a curve which is used to project back to the original speed. This is essentially what Shot Spot and Hawkeye and the like use to calculate where a ball will land. Such methods are more accurate — but not perfectly accurate. In every case, there are calibration errors, and peculiar atmospheric conditions, and different spins on the ball.

What it all boils down to is this: Different radar guns are different. The two fastest men’s serves ever recorded, as of when this story was first written, were both made on the same model of radar gun. From what we gather, it’s one of the complex curve guns, so it may actually be more accurate than all the others. But to compare radar gun readings from different guns is comparing apples and oranges. Or, at least, comparing Delicious and Granny Smith apples: It’s a fruit of a whole different color.

RANKINGS

Estimated ATP World Tour Rankings

As of August 20, 2014

Rank &

Prior…Player………..Points

1..(1) Djokovic……….12770

2..(2) Nadal………….10670

3..(3) Federer…………7490

4..(4) Wawrinka………..5985

5..(5) Ferrer………….4765

6..(6) Raonic………….4225

7..(7) Berdych…………4060

8..(8) Dimitrov………..3540

9..(9) Murray………….3150

10.(10) Tsonga………….2920

11.(11) Nishikori……….2680

12.(12) Gulbis………….2580

13.(13) Del Potro……….2410

14.(14) Gasquet…………2360

15.(15) Isner…………..1925

16.(16) Cilic…………..1845

17.(17) Fognini…………1835

18.(18) Robredo…………1825

19.(19) Bautista Agut……1800

20.(20) Anderson………..1775

21.(21) Lopez…………..1770

22.(23) Dolgopolov………1580

23.(24) Youzhny…………1540

24.(22) Monfils…………1530

25.(25) Kohlschreiber……1505

26.(26) MayerL………….1354

27.(27) Benneteau……….1285

28.(28) Almagro…………1250

29.(29) Karlovic………..1220

30.(30) Simon…………..1180

DRAWS

Winston-Salem — Week of August 18, 2014

…………………3R………………QF

1 Isner…………..(1)Isner…………Isner

13 Kukushkin………(13)Kukushkin

10 Andujar………..(10)Andujar

7 Rosol…………..(7)Rosol…………Rosol

3 Robredo…………Mahut

14 Seppi………….(14)Seppi………..Seppi

9 Lu……………..(9)Lu……………Lu

8 Granollers………(8)Granollers

6 Sousa…………..Janowicz…………Janowicz

12 Roger-Vasselin….(12)Roger-Vasselin

15 Nieminen……….(15)Nieminen

4 L Mayer…………Goffin(Q)………..Goffin

5 Garcia-Lopez…….(5)Garcia-Lopez…..Garcia-Lopez

11 Young………….(11)Young

16 Johnson………..Querrey………….Querrey

2 Anderson (WC)……(2)Anderson

STATUS OF SEEDS:

1 Isner

2 Anderson (WC)……lost 3R (Querrey)

3 Robredo…………lost 2R (Mahut)

4 L Mayer…………lost 2R (Goffin)

5 Garcia-Lopez

6 Sousa…………..lost 2R (Janowicz)

7 Rosol

8 Granollers………lost 3R (Lu)

9 Lu

10 Andujar……….lost 3R (Rosol)

11 Young…………lost 3R (Garcia-Lopez)

12 Roger-Vasselin…lost 3R (Janowicz)

13 Kukushkin……..lost 3R (Isner)

14 Seppi

15 Nieminen………lost 3R (Goffin)

16 Johnson……….lost 2R (Querrey)

******** SCORES ********

WEDNESDAY

Winston-Salem

Singles – Third Round

(1) J Isner def. (13) M Kukushkin 6-1 7-6(7-3)

S Querrey def. (2) (WC) K Anderson 7-6(7-4) 6-4

(5) G Garcia-Lopez def. (11) D Young 6-7(4-7) 6-3 7-6(8-6)

(7) L Rosol def. (10) P Andujar 1-6 6-2 6-2

(9) Y Lu def. (8) M Granollers 6-1 6-2

(11) D Young def. (5) G Garcia-Lopez 7-6(7-4) 3-6 7-6(

J Janowicz def. (12) E Roger-Vasselin 4-6 6-3 6-4

(14) A Seppi def. N Mahut 6-4 7-6(9-7)

(Q) D Goffin def. (15) J Nieminen 6-4 4-6 6-4

Doubles – Quarterfinal

Mergea/Sousa def. (WC) Monroe/Young 6-2 1-6 12-10

Topics: Atp, Donald Young, John Isner, Kevin Anderson, Marcel Granollers, Sam Querrey, Tennis, Tennis News, Winston Salem Open

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10sBalls_com says:

August 20, 2014 at 8:04 pm

MEN’S TENNIS RESULTS FROM THE WINSTON-SALEM OPEN- http://t.co/ZBS0ceYZQn #tennis #winstonsalemopen #ATP @ATPWorldTour #tennisresults