FIFA World Cup 2018: The science behind Cristiano Ronaldo’s dreamy free-kick against Spain

The technique: Where most players use their instep to slice the ball, Ronaldo strikes using the top of his toes and hits right through the line rather than around the ball. He moves the boot slightly from the middle to get further curve. He pushes it into the ground so when he plants his standing foot next to the ball it pops up, giving the shot something of the quality of a volley, besides imparting dip. The ball bends, laterally as well as vertically, Also, he tries to hit the ball with as little spin as possible, so when the ball is hit without spin, it’s more susceptible to wobble unpredictably.

The maths: When Ronaldo is in the middle of that meditative, shut-out-of-the-world trance, he must by doing quick maths. Busquets is 6 feet two. When he jumps, he will be at least eight feet off the ground. So Ronaldo has to propel the ball over over eight feet, which incidentally is the height of the post too. But he needs to bring it down by least a foot for the ball to crash into the net. So he whisks the ball almost nine feet high before it plunges mid-air by a couple of feet. Also, he has to factor in the deviation . Too little swerve would mean the ball would crash into the post or miss it, too much would mean the goalkeeper can stretch and thump it away. Ronaldo curved the ball just enough to beat both—the angle of deviation a metre or a trifle more perhaps.

The velocity: Ronaldo’s free-kicks have vicious pace—the latest pearler travelled at nearly 50mph. But for someone who hits at this pace, he doesn’t have Carlos’s oak-like thighs or extravagant follow-through, which means he doesn’t use much of his body. Rather a fluid, decisive swing of his right leg. To borrow from cricket—sheer timing. The power also strips the goalkeepers of reaction time. And power with precision, swerve and dip make goalkeepers’ life hellish.