Forehand Trajectory of the Big Four

[GameSetAndMath]

The following graphic was shown on TV recently during the telecast of one
of the matches in the current AO. It shows a chart depicting the
the average net clearance, rpm and bounce height of the forehand shots hit by
the big four players during 2013.

http://i.imgur.com/EsVokcc.jpg

It says Nadal's net clearance is 90 inches. That is 7 and half feet. Is that real?
When Nadal hits a forehand, at the time when it crosses the net is the ball
that high from the ground? Seems too high to me.

What exactly is the definition of the term "Net Clearance"?

Apparently, Nadal has the highest net clearance and Fed
comes next. Djokovic's clearance is even below that.
Murray's is even below that.

Obviously, having it very close will lead to lot UFEs with the ball hitting the net.
But, is not it also true that it is undesirable to have huge net clearance (as it
would almost amount to moonballing and/or playing badminton).

What would be the optimal net clearance.

Also, I suppose flat shots will tend to have less net clearance than
top spin shots. Am I correct on that?

 

[brokenshoelace]

The following graphic was shown on TV recently during the telecast of one
of the matches in the current AO. It shows a chart depicting the
the average net clearance, rpm and bounce height of the forehand shots hit by
the big four players during 2013.

http://i.imgur.com/EsVokcc.jpg

It says Nadal's net clearance is 90 inches. That is 7 and half feet. Is that real?
When Nadal hits a forehand, at the time when it crosses the net is the ball
that high from the ground? Seems too high to me.

Apparently, Nadal has the highest net clearance and Fed
comes next. Djokovic's clearance is even below that.
Murray's is even below that.

Obviously, having it very close will lead to lot UFEs with the ball hitting the net.
But, is not it also true that it is undesirable to have huge net clearance (as it
would almost amount to moonballing and/or playing badminton).

What would be the optimal net clearance.

Also, I suppose flat shots will tend to have less net clearance than
top spin shots. Am I correct on that?

Flat shots do have less net clearance. So it's not surprising to see the guys who play with the most spin have the most net clearance (remember that thread where I argued that there's no way Djokovic hits with as much spin as Federer?).

However, yeah, 90 inches is absolutely ridiculous and definitely inaccurate. 90 inches is exactly 7.5 feet, as you mentioned. Think about it that way: How tall is Nadal? About 6 foot 1? So most balls he's hitting are virtual lobs that fly at a height above his head? Just visually, you can tell that this is wrong.

 

[GameSetAndMath]

Not just Nadal's; all the data in the net clearance column seems too high to me.
It does not match with the common sense visual observation that we get as someone
who watches these matches.

So, there is something seriously wrong here.

If I assume that they forgot to put a decimal point, the clearance looks too small (even if
I interpret it as the height from the top of the net).


I don't know what is going on here.

 

[Luxilon Borg]

The following graphic was shown on TV recently during the telecast of one
of the matches in the current AO. It shows a chart depicting the
the average net clearance, rpm and bounce height of the forehand shots hit by
the big four players during 2013.

http://i.imgur.com/EsVokcc.jpg

It says Nadal's net clearance is 90 inches. That is 7 and half feet. Is that real?
When Nadal hits a forehand, at the time when it crosses the net is the ball
that high from the ground? Seems too high to me.

Apparently, Nadal has the highest net clearance and Fed
comes next. Djokovic's clearance is even below that.
Murray's is even below that.

Obviously, having it very close will lead to lot UFEs with the ball hitting the net.
But, is not it also true that it is undesirable to have huge net clearance (as it
would almost amount to moonballing and/or playing badminton).

What would be the optimal net clearance.

Also, I suppose flat shots will tend to have less net clearance than
top spin shots. Am I correct on that?

Flat shots do have less net clearance. So it's not surprising to see the guys who play with the most spin have the most net clearance (remember that thread where I argued that there's no way Djokovic hits with as much spin as Federer?).

However, yeah, 90 inches is absolutely ridiculous and definitely inaccurate. 90 inches is exactly 7.5 feet, as you mentioned. Think about it that way: How tall is Nadal? About 6 foot 1? So most balls he's hitting are virtual lobs that fly at a height above his head? Just visually, you can tell that this is wrong.

ESPN had totally different numbers when I saw the graphic. The range was 33 inches to 27 inches. This is off.

 

[brokenshoelace]

ESPN had totally different numbers when I saw the graphic. The range was 33 inches to 27 inches. This is off.

Yeah this sounds more reasonable.

 

[GameSetAndMath]

I remember seeing this kind of unreasonable numbers and that is why I created this
thread. May be they fixed later? I saw this chart only once on TV.

 

[brokenshoelace]

I remember seeing this kind of unreasonable numbers and that is why I created this
thread. May be they fixed later? I saw this chart only once on TV.

One explanation could be that they said 90 inches instead when in fact they meant centimeters. 90 centimeters roughly equals 35.4 inches, which definitely sounds much more reasonable. So maybe the numbers are accurate, but the unit of length isn't.

 

[brokenshoelace]

OK, so upon further inspection, I stumbled upon this (http://espn.go.com/tennis/french12/story/_/id/8019942/french-open-why-rafael-nadal-needs-break-habits) article on ESPN's website. It's from a couple of years ago. The article states that Nadal's average net clearance at Rome in 2012 was 27 inches. If that's true, I would suspect his average net clearance at the AO this year is even less than that since he's not hitting with as much spin as he does on clay.

 

[GameSetAndMath]

27 inches sounds reasonable.

BTW the chart shown on tv is supposed to be the average for the 2013 season and
has nothing to do with the current AO. However, still the numbers are not believable
and so someone messed it up.

 

[Luxilon Borg]

I remember seeing this kind of unreasonable numbers and that is why I created this
thread. May be they fixed later? I saw this chart only once on TV.

I am glad you did... This is interesting.

 

[Luxilon Borg]

I remember seeing this kind of unreasonable numbers and that is why I created this
thread. May be they fixed later? I saw this chart only once on TV.

One explanation could be that they said 90 inches instead when in fact they meant centimeters. 90 centimeters roughly equals 35.4 inches, which definitely sounds much more reasonable. So maybe the numbers are accurate, but the unit of length isn't.

Think that May be it.

 

[GameSetAndMath]

I remember seeing this kind of unreasonable numbers and that is why I created this
thread. May be they fixed later? I saw this chart only once on TV.

One explanation could be that they said 90 inches instead when in fact they meant centimeters. 90 centimeters roughly equals 35.4 inches, which definitely sounds much more reasonable. So maybe the numbers are accurate, but the unit of length isn't.

Think that May be it.

I don't know. The bounce height given in inches look reasonable. I doubt they would
have tried to use different units for length measurement in different places. I think the
ESPN statistician goofed off.

 

[GameSetAndMath]

It was Cliff Drysdale who was reading off this chart and simply coolly read off without
getting perturbed by the numbers at all. He is a former tennis player apparently.

 

[brokenshoelace]

It was Cliff Drysdale who was reading off this chart and simply coolly read off without
getting perturbed by the numbers at all. He is a former tennis player apparently.

LOL yeah. Funniest part is I Googled this to see whether people reacted, and someone made a thread about this in a different tennis forum (without questioning the numbers) and the first reply was: "Didn't we know this already?"

Six replies later and still nobody thought something was wrong with these numbers, until somebody humorously said: Maybe they just took into the consideration the shots that end up in the stands? To which another poster replied: In which case Federer should have the most height.

 

[brokenshoelace]

By the way, I wouldn't take any of this data seriously because no way does Nadal AVERAGE 4300 rpm's over an entire season. Sounds ridiculous. It's not just that net clearance that is wrong. His average is definitely somewhere in the 3300 rpm range.

 

[GameSetAndMath]

By the way, I wouldn't take any of this data seriously because no way does Nadal AVERAGE 4300 rpm's over an entire season. Sounds ridiculous. It's not just that net clearance that is wrong. His average is definitely somewhere in the 3300 rpm range.

Well, at least it is in the believable range (unlike net clearance). Also, this is taking into
account only forehand shots. While I don't know what the average would be, it is possible
that Nadal's average forehand topspin shot has that much RPM. I read somewhere that
he even hits 5500 rpm shots sometimes. Hence, it is quite conceivable that the average
can be 4300.

 

[brokenshoelace]

By the way, I wouldn't take any of this data seriously because no way does Nadal AVERAGE 4300 rpm's over an entire season. Sounds ridiculous. It's not just that net clearance that is wrong. His average is definitely somewhere in the 3300 rpm range.

Well, at least it is in the believable range (unlike net clearance). Also, this is taking into
account only forehand shots. While I don't know what the average would be, it is possible
that Nadal's average forehand topspin shot has that much RPM. I read somewhere that
he even hits 5500 rpm shots sometimes. Hence, it is quite conceivable that the average
can be 4300.

Just checked, Nadal's average forehand RPM is reported to be 3200 just about everywhere. 4300 is insane when you factor in the shots he flattens out, the shots he decides to go for a winner on, etc...

 

[GameSetAndMath]

For those of you watching the Nadal- NeiKishori game just a few minutes ago,
Cliff was talking about the net clearance along with Darren and they showed the
graphic that I posted in my OP. Darren said nice graphic. All of this happened
during the break at 5-4.

So, they have not corrected anything. They stand by the chart.

I looked at the numbers carefully again when they showed. It is exactly the
same as what I posted with Nadal's at 90 inches and so on.

 

[brokenshoelace]

For those of you watching the Nadal- NeiKishori game just a few minutes ago,
Cliff was talking about the net clearance along with Darren and they showed the
graphic that I posted in my OP. Darren said nice graphic. All of this happened
during the break at 5-4.

So, they have not corrected anything. They stand by the chart.

I looked at the numbers carefully again when they showed. It is exactly the
same as what I posted with Nadal's at 90 inches and so on.

...The Worldwide Leader in Sport.

 

[GameSetAndMath]

If any of you are recording this match, you should be able to freeze it at the particular
frame and confirm that the numbers shown on TV are exactly the same as in the graphic
posted in my OP.