For my birthday last year my kids bought me a tennis lesson. I walked onto the court, my arthritic right knee wrapped in neoprene, my right arm strapped just above my overstressed forearm. The twentysomething pro shook my hand and asked: "What are your goals?"

Goals?

I've played tennis some since I was 12, regularly since I was 30, passionately since I was 40. I'm 51 now, a good quarter-century past the physical peak for a tennis player and hampered by two chronic injuries. Since I had not taken tennis seriously until so late, it happened that I was now better than I'd ever been. I already knew the basic strokes, plus most of the add-ons -- the slices, topspins and drop shots that mark the beginning of advanced play. Given my age, and the fact that my knee and elbow vulnerabilities limited how many hours I could log on the court, it would be fair to wonder how much better I could hope to get.

So what was I doing there?

I thought for a minute, then said, "I want to win."

That was a little glib. I love playing tennis even when I lose -- kind of. I don't dance, but I do on the tennis court: Step-step-step slam. Step-step-step slam. When you get it right, your body rocks and rolls across the court, your driving legs transitioning flawlessly into a twisting leap of a swing, all in time to the bouncing ball, which sizzles off your racket, cutting gorgeous angles, painting lines, blasting past your opponent.

That's where the winning comes in. If a perfect forehand slashes across an empty court, does it make a sound? In a word, no. The larger beauty of a shot comes not from the stroke itself but from the way it manages to elude, overpower or otherwise frustrate a worthy opponent. Tennis is hand-to-hand combat by other means. The punches you throw just happen to be thrown long-distance at the end of a racket across a braided net. You can jab and spar and move your feet, but the goal, always, is a knockout.

This fierce will to vanquish can be seen not just on the hallowed center courts of Flushing Meadows or Roland Garros, but in any run-of-the-mill racket club. Take the one on Lee Highway in Fairfax. In the perpetual dusk of the dozen domed courts, from 6 a.m. until 11 p.m. seven days a week, you can find all the fist-pumping, primal-screaming, showboating intensity of a U.S. Open final, minus only the million-dollar purses, the 135-mph serves and the thousands of screaming fans. The fact that there may not be a single person -- aside from the (usually) middle-aged athletes sweating and grunting between the white lines -- who cares even a little about the match's outcome (no, not even the spouse at home who may or may not wanly feign interest) does nothing to diminish the intensity of the desire to win.

This reaches its ultimate expression in the unofficial club tennis ladder. Tracked via Web-based software on TennisRank.com, a couple of dozen players battle week in and week out to claim or defend higher ground on the ladder. Based on the prematch jitters, the hard-charging, hard-slamming, leave-nothing-on-the-court style of play and the barely masked despair of the loser, you'd think it was Hamburger Hill being defended, not the difference between being No. 9 or No. 10 on some virtual hierarchy.

I've been playing some of the guys on this ladder for years. We know one another intimately -- the precise velocity and spin of our serves; the relative weakness of our backhands and forehands; our quickness, or lack thereof, in each and every direction on the court. I know that the guy with the cannon forehand -- the one who had played competitively in some Nordic country -- has an extra 30 pounds that will eventually drag him down if you can just hang around long enough. I know that the guy with the huge topspin can't hit a short ball, and the guy with the 107-mph serve can be counted on for three unforced errors a game. Beyond that, I know little more about them than occupation and marital status. What goes on outside the glowing cave walls of the tennis bubble, say a Supreme Court nomination or the invasion of a Middle Eastern country, may merit a passing comment. But the serious discussion is reserved for who's on a hot streak, who's developing sportsmanship issues, who suddenly popped an extra 5 mph on his serve.

And then there was the new guy -- the one with the antique racket and the Popeye calf muscles. He looked to be 40, couldn't have been over 5-foot-6. He said he'd been in this country for years, but sometimes his Spanish accent made him hard to follow. (One thing I did pick up clearly: He had been a champion sprinter in high school.) Each of us had to learn the hard way that his cream-puff shots were a cruel hustle: The harder we slammed them back, the easier he made beating us look. He got to every ball and hit every line. I knew him better than most -- we played every Tuesday. I learned quickly to curb my idiotic aggression, to keep the ball in play and wait for a sure winner. It was an effective strategy in the sense that it led to titanic battles with endless rallies. The few times I managed to eke out a win, he'd say something deflating -- "Very good! And at the end, I was really trying . . ."

But I almost always lost. Oh, it was bitter: Sometimes I'd be playing out of my head and go up a couple of breaks of serve, a game away from victory. But he simply made ever more unbelievable retrievals, and hit ever more uncanny winners until he pulled even, then put me away. The lost opportunities haunted me -- an easy volley dumped into the net, an open forehand sprayed wide. A victory that got away.

I watched with clandestine glee as he joined the tennis ladder and rung by rung made fools of all those so certain they could overpower him. Defeated opponents gathered in his absence, muttering and sputtering and wondering, communally, how to beat him. Some were convinced that his soft shots just temporarily put them off their game (the self-delusionists). Others that they only needed to hit harder (the macho losers). They thought about him on the commute to work, and in the small hours when they twisted restlessly in the dark.

But maybe I'm projecting. I can speak only for myself when I admit that if I won a match, I'd find myself calling up the ladder's Web site on any pretext -- or none whatsoever. I'd sign in to ogle the lovely juxtaposition of my name beside that better-than-last-week number. I'd study the movement among the other players and look covetously at the even-better number beside the name of my next opponent.

If I lost, however, I could not bear to look. If I had to call up the site to schedule a match, I'd avert my eyes when the abhorrent list appeared, as if numeric proof of my slippage could turn me to stone.

Like I said, I want to win.

And to win more, I needed to get better. But how?

Maybe this lesson would help.

It never ceases to amaze me how much I know about tennis, and how little. I know enough to learn something every time I watch a professional match: Look at how so much of the serve is about what happens after the racket hits the ball. Look at how the one-handed backhanders flick the racket over their shoulder, as if they were slapping some insolent cavalier upside the head with the back of their hand. Look at how the player's empty left hand balances the backhand slice, arching gracefully in the opposite direction of the racket hand, like she's a ballerina doing a curtsy.

I learn something every time I pick up a tennis magazine: Toss the service ball slowly, with the arm straight, palm up, fingers extended, as if you were elevating a silver platter; position yourself for an overhead by raising your free hand to the ball, as if you were about to make a catch in center field.

And I learn something in my birthday lesson: I'm too close to the ball on my backhand, not catching it low enough in its arc.

I practice all of this, with my wife, with my kids (tennis players all), in my matches. We even spring for a small ball machine, justifying the $700 price tag as the equivalent of a dozen lessons. And, as my elbow and knee get worse, I get better.

At least I think I do.

Then I play a guy I haven't played in six months, a guy I battled for every point and every game when we last played. I hit great, a half-level above my old game. It's not just a feeling -- I can pinpoint exactly what I'm doing better in each of my strokes.

I win the first set, barely. I lose the second in a tiebreaker. We battle for every point, every game.

He must have gotten a lot better, too, I think. Then a disturbing doubt occurs: Have I been kidding myself?

I have come to worship at the wall. It is gray dawn, and the wall is big and green, riddled with spots where the paint has peeled and the concrete has chipped beneath it. It looks for all the world like a firing squad has done years of pitiless work here, but in fact it is just a place where people came to pound tennis balls into something hard and flat that will reliably pound them back.

For some reason, I'm here before anyone else in my house is even out of bed. I've been thinking lately about one of those standard sound bites of tennis advice I've heard in one form or another all my life. "Look the ball into the racket." Maybe I'm thinking about this aphorism because I've been watching Wimbledon, where Roger Federer is working his way through the tournament with the most perfect form in the sport. Even at full speed, you can see how his gaze lingers at the point of impact, as if momentarily lost in an abstract consideration of the physics involved when a tightly strung racket slams into a flying spheroid of synthetic rubber and neon yellow fuzz. As if he has lost all interest in the trajectory of the ball off his racket, where it might land on the other side of the court, or what his opponent might do about it. As if there is absolutely nothing of interest in the wide world but that fraction of a second of compression and expansion that can launch a tennis ball at speeds exceeding 100 mph.

Maybe I'm thinking that although for four decades I have always believed I've been keeping my eye on the ball, in fact I have not.

I begin to work. Slam, step, slam, step, slam . . . It hasn't been more than two minutes before the first drops of sweat fall from my forehead to spot the cracked pavement at my feet. I keep at it until finally I hit the ball high, over the wall, then walk, sweat-soaked and winded, to retrieve it. Hitting against a wall is like jumping rope, or punching a speed bag, instantly exhausting. But I'm happy; I can feel myself leaning into the swing and being rewarded with the satisfying twang of the strings and thud of the ball.

Still, I can't absolutely swear that I'm keeping my eye on the ball until it hits the racket face. In fact, I suspect that at the last instant there's something like a flinch, some ingrained need to turn my head to watch the flight of the ball. I try to concentrate. No matter what, I tell myself, I will not look away from the impact. I hit a few strokes and feel the flinch. I stop, put my hands on my knees and breathe slowly. I listen to a cardinal calling in the stand of oaks beyond the fence, the hum of a dragonfly floating on the heat rising off the court, the faint sounds of a car accelerating. I steel myself and swing again, willing my head to stay still as the racket hurtles toward the incoming ball. And then I see something I have never seen before. A yellow streak. I hit again, to make sure, and there it is, that streak of color that is the ball compressing to a point then blasting off the tight trampoline of nylon strings. I hit again and again, forgetting everything but that single focal point. I feel my body moving in sync around the pivot of that steely focus, everything cocked and ready to snap at the optimum moment, my eyes lasered on the point where it all comes together. Bang, zoom, the ball flashes to the wall with a heavy whap, and I understand that, until this moment, I have never really done it right.

My son is back from a week at tennis camp. He played five hours a day in 90-degree heat, and I wish I could have gone, too. I persuade him to come with me to the neighborhood court and play a full set. It's the first time we've done more than hit or play a few points. I know he likes to win, and I don't want to discourage him. He's 14, just over 120 pounds. But already he has the kind of strokes I see on TV, and can hit a serve at close to 100 mph. I know he has something I never had, and never could acquire. It's what the pros call a loose arm, enabling the whip-like motion that can allow 120 pounds to hit like 180. He was simply born with it, and what he does with that ability is purely a matter of his own desire.

Inevitably he'll beat me, but not today. He may be able to hit it harder than I can already, but he doesn't know the chessboard like I do, or have the confidence and consistency to work the angles, patiently, knowingly waiting for that piece of open court to deliver the knockout. He doesn't yet have the drive, or the work ethic, or maybe just the crazy love of the game, to wake up before first light, go to the wall and hit and hit and hit until he sees a vision of his true potential.

But one thing I notice about three games in: I'm playing full out, with all the guile and viciousness I can muster, and it's not a wipeout.

On one point I slam it in the corner, but somehow he gets there and whips a death ray out wide. I have no intention of giving him the winner, and I start to dig for it at top speed. I feel a twinge in my knee. A reminder: I won't be able to play this game forever. In fact, some day soon I may face a decision: Quit early and walk without a cane until I'm 80. Or not.

But that isn't what I'm thinking. What I'm thinking is: I hope I can keep going at something like full speed long enough so that, one day, my son will walk out on the court and blow me away.

Tom Shroder is editor of the Magazine.