Watch the evening sportscast for five minutes and you will encounter the ubiquitous sports jargon that effortlessly streams from the lips of any given reporter: Morneau went "yard," Ponder threw a "pick-six" and Parise "lit the lamp with a one-timer through the five-hole."

With a little help from a translator, even nonfans can learn the lingo and in no time be standing around the water cooler dropping how much of a crime it was for Kevin Love to be "T'd up" for a hard foul in the previous night's game.

But let's not confuse these midlevel colloquialisms with the more hard-to-define insider terms that are understood only by those who have played the game or been extremely close to it. You might have heard someone say that Tom Brady has "great vision" or Stephen Strasburg has a "live arm" or diminutive golfer Adam Scott is "sneaky long."

We kinda sorta get the gist of these descriptors — because we see the resulting touchdowns, fastballs, and yardage — but the fact is, most of us would have difficulty articulating what exactly a "live arm" is and how it contrasts to, say, what would be the contrast — a dead arm?

Tennis, too, has one of these enigmatic expressions, and grasping its meaning goes a long way toward understanding why Rafael Nadal has won seven French Open titles in the eight times he has played the tournament. You may have heard it said that Nadal hits a "heavy ball."

But what does that mean? Does Rafa train by hitting tennis balls that weigh more than the standard 2 ounces, sort of like a boxer punches a heavy bag or a slugger takes warmup swings in the on-deck circle with a heavier bat? Well, not exactly.

Nadal's heavy ball is all about the force with which he strikes the ball on his groundstrokes, especially his ferocious forehand, which results in his opponent feeling like the ball he is attempting to hit back is "heavier" than the typical shot from another player.

It is important to note that pure velocity is not the sole factor in the weightiness of Nadal's groundstrokes. It is the combination of speed and topspin that elevates the Spaniard into a category of his own.

One analysis of Nadal's forehand clocked the ball rocketing off his racquet at nearly 100 mph and spinning at an average rate of 3,200 rpm. That sounds amazing, but when you find out that the latter number is 20 percent greater than his rivals, Roger Federer and Novak Djokovic, and nearly 50 percent higher than last generation greats Pete Sampras and Andre Agassi, then you know it's amazing.

How does Nadal produce this heavy ball? It's the tremendous racquet-head speed that he generates, along with the whipping shape of his strokes, along with his extreme grip, along with the way he violently uncoils his torso, along with the polyester string he uses, along with ... well, just do a search for "Speed and Spin: Nadal's Lethal Forehand" and a New York Times video will show you why.

Clay courts provide the perfect surface for the English (Spanish?) that Nadal puts on his ball. The topspin that Rafa imparts causes the ball to jump wildly off the gritty surface with the full intention of doing the same off your racquet strings unless you strike it back with equal and opposite force. Over time, countering Rafa's heavy ball with your own becomes exacting and exhausting, and before you know it, you're shaking hands with him at the net, having crashed and burned in straight sets.

A heavy ball alone has not made Nadal the best clay-court player ever (my apologies to Bjorn Borg fans, but the Spaniard has surpassed the Swede). Rafa also possesses a strong and agile body, an indomitable will, superb poise under pressure and, as if that weren't enough, a respect for the game and his opponent.

Basically from the day he came on tour, no one has found a way to master Nadal on clay. To say that his occasional loss on the surface (like in the final of Monte Carlo earlier this month after having won a record eight straight times) is the exception rather than the rule does not draw a wide enough distance between "exception" and "rule."

His tour-leading six titles this year are all the more remarkable considering he was sidelined with injury for seven months from July of last year to February of this year. With his chief rivals either overmatched (Federer is 2-for-15 vs.Rafa on clay), injured (Andy Murray) or inconsistent of late (Djokovic), Nadal enters Paris as not just the favorite for an eighth title but a heavy one indeed.

During his 13-year professional tennis career, Minnesota's David Wheaton reached the third round in singles and semifinals of doubles at the French Open. Find out more at davidwheaton.com.