[Robbie] Here's something you probably won't see

at the World Cup this year. It's called a gol olimpico.

It's a direct goal scored off a corner kick.

See how the ball curves?

To pull it off, a player needs to kick the ball

from the corner of the field and bend it into the goal

without the assistance of any other players.

They're super rare and when they do happen,

it's usually an accident. I mean look at this.

You're aiming for an opening you can't even see.

The only way to do it is to bend the ball.

You know, like David Beckham.

[Announcer] David Beckham swinging it right in.

(crowd cheers)

Gol olimpicos are almost impossible. To find out what

makes them so rare, I kicked the ball with an Olympian.

[Brandi] Yes!

Got some pointers from a pro.

A lot of hip motion through the ball.

[Robbie] And talked soccer ball aerodynamics

with a scientist.

[John] So, as you start changing the surface

the aerodynamic properties change a little bit and

that effects the flight of the ball.

really played soccer

since I was a kid. So, I got some tips from Brandi Chastain.

She's a two-time Olympic gold-medalist

and World Cup champion. These days, she's an assistant coach

for the Women's soccer team at Santa Clara University.

[Brandi] Then you'll come around the ball.

Brandi, you've scored a few goals in your life, right?

A few, one or twice.

Alright.

Yeah, Chastain scored the game winning penalty kick

that won the World Cup for the U.S. Women's team in 1999.

She showed me the finer points of bending a corner kick.

[Brandi] Well, first I'll ask you are you

left-footed or right-footed?

Definitely right-footed.

Then we're on the proper corner.

[Robbie] One of the first things to do is figure out

which way the wind is blowing.

You recognize that the wind, right, the wind is going

to be pushing into the goal. So, it's important

that you start the ball out just outside of the goal.

So, that the bend will bring it back in and by bend

do you know what I mean by that?

[Robbie] I think you're meaning I need to put

some swerve on the ball.

Yeah, you need to put a little love, a little texture.

[Robbie] Easy enough, right?

[Brandi] You've got some things going for you.

Good noises, liked that. You've gotta have a little

oomph on it. You've got good bend. Now, we just have

to make sure that we get you in the right direction.

[Robbie] Okay, so my first attempts were not great.

Just getting the ball out there was clearly going

to be a hurdle.

[Brandi] Aim right and it's gonna come back this way.

Oh, come back.

[Robbie] (groans)

[Brandi] Now, it's just the aim.

[Robbie] We've got the distance.

Now, we just need that swerve.

Chastain showed me how she divides the ball into sections.

So, she can kick it with power and precision.

[Brandi] The ball can be split into four quadrants

and basically then manipulated

by where you hit it.

So, if you hit the ball straight through the middle

it will have this kind of motion. If you hit the ball

underneath, it will have this kind of motion.

And likewise, from one side to the other it will have

this kind of curving motion.

[Robbie] And now, for the tricky part.

[Brandi] You take that and now you create like

the third plane which is you go from one plane up through

another plane. Now, you not only get the spin, but you

get the up and then the down. You can basically

take the ball and make it turn whatever way you want it to

depending on the placement of your foot on contact.

So, the ball can do all kinds of amazing things

depending on how you strike it.

[Robbie] So, what do I need to work on?

Well, it's not just you, Robbie, what you need to work on.

It's what all players need to work on is the balance

between the force that you put on the ball and the finesse

that you give it. Kind of the love that you give the ball.

[Robbie] As Chastain says, It's force and finesse.

But, in scientific terms, it's something called

the Magnus Effect.

[John] So, I've got the ball spinning like this.

The Magnus Effect says if the air is pushed off to the side

to the side over here, the air that's being pushed this way

has to be pushing the ball in the opposite direction

that's Newton's Third Law. So, if you see a ball coming

at you spinning like this, the front part of the ball

tells you which way it's gonna wanna move.

So, if it's spinning like this it's gonna wanna move

the direction my finger's showing.

[Robbie] We're basically talking about the effects

of the spin. It's the same physics behind a curve ball

in baseball or a slice in golf. It's even used

by some basketball players.

Without the Magnus Effect, there would be no gol olimpicos.

Which isn't to say that they're easy to master.

I had every advantage when I was trying. The wind was

in my favor. There was nobody in the goal box. And I had

expert advice on spin from Chastain. Maybe it was the ball?

Now, I know what you're thinking. This guy just isn't very

good at soccer and yes, you are totally right.

But, the ball's design, particularly the number of panels

and seams, can make a big difference in the way it flies.

Scientists at places like MIT and NASA have actually

looked at this and the issue is something

they call roughness. And anyone who remembers the

controversial 2010 World Cup Jabulani ball,

knows exactly what I mean.

[John] The reason there was controversy over Jabulani

is when you start reducing the number of panels on a ball,

you run the risk of making it too smooth.

[Robbie] Think back to the Magnus Effect, remember how

it whips air in the direction of its spin?

That's only true for rough balls, ones with lots

of panels and seams.

But, smoother balls, like the Jabulani, they deflect air

less consistently and if the ball is perfectly smooth,

it can actually whip air in the opposite direction.

Producing a Reverse Magnus Effect.

Now, spin isn't the only way to manipulate a ball's

flight path. If you want it to move unpredictably,

you can kick it with little to no spin.

That's called a knuckle ball, just like the one in baseball.

Chris Wehan, a midfielder for the San Jose Earthquakes,

showed us how it's done.

Simply come back and strike straight through the ball.

Hitting it more with your laces rather than with the inside

of your foot is kind of the best way to hit it.

You just kind of let the seams and the design of the ball

kind of do the magic.

[John] So, he kicked the ball right through the center

of the ball. Right through it's center mass, you're gonna

have it come off the boot with very little spin and

if it's got just a little bit of spin you can alternate

where those smoother or rougher areas are on the sides

and as it starts to separate with the boundary layer

delayed on the rough side that means it's gonna wanna move

toward the rough side. So, you can get this wobble happening

when the ball has a little bit of turn in it.

[Robbie] And that wobble can be an advantage

for penalty kicks. But, back to my quest to kick

the elusive gol olimpico.

Chastain brought in a ringer, to show me a few more things.

C'mon Kelsey.

This is Kelsey Turnbo. She was our WCC Freshman Player

of the Year. She also happens to play with our one of our

youth national teams here for the U.S. Technically, she's a

lefty, but she can do this right-footed as well.

[Robbie] Turnbo definitely had better form than me.

And better finesse.

Plus, she can kick with both feet. She can really bend

the ball towards the goal and her shots went in.

After dozens of tries, I finally managed to kick

a gol olimpico myself.

Alright, so it bounced a bit and it was hardly under game

conditions. The goal was wide open. So, if you see one

in a game, remember that the reason they're so rare

is that all the skill and science of soccer have to come

together perfectly and that's why they're almost impossible.

[Brandi] When you look at the elite players,

they naturally will factor those things in because they've

done it multiple times. They understand the elements and

they understand the circumstance and when it is the right

time and when it's not the right time. And if it isn't

the right time, you'll absolutely, you'll see it.

You'll see the outcome because it won't be close.

And when it is the right time, it's a thing of beauty.