Rafael Nadal, left, and Novak Djokovic will face off Monday in the U.S. Open final. Getty Images

Here was the plan: During Saturday's U.S. Open men's singles semifinals, I would meet with Rod Laver. We would talk a bit before the matches began, and again after the first semifinal match, and then speak once more after the second semi, and through those discussions we would have a pretty good idea of what Rod Laver expected going into Monday's U.S. Open men's singles final.

I am making that sound very routine. It was not at all routine. At least not for me.

Let me backtrack for a moment. I grew up in a tennis house. My dad has coached high school tennis in Cambridge, Mass., for 40 seasons. I have vivid memories of being a little kid, watching Bjorn Borg, John McEnroe, Jimmy Connors, Ivan Lendl, Pete Sampras, Andre Agassi.

Champions all, dazzling in their own ways, but I always felt like I missed something, because my dad never stopped talking about the champion I never saw.

Legend Rod Laver Associated Press

Rod. The Rocket. King of the Aussies. The way some dads talk about Jim Brown or Joe DiMaggio, my dad talked about Rod Laver.

I tried to compensate. I had the Laver sneakers, like a lot of people—those timeless mesh Adidas ones that somehow looked sharp in both a business meeting and a canoe. I'd read "The Education of a Tennis Player," Laver's book with Bud Collins. But I'd never met him, and because of the way my father spoke about him, he'd always felt a little unreal, supernatural. I certainly knew Laver's résumé. Eleven major-tournament singles victories, a brilliant career that straddled tennis's evolution from an amateur sport to the Open era. Like all tennis fans, I knew Laver had won all four majors in a single calendar year, a grand slam. He'd done this twice, in 1962 and 1969.

And there he was Saturday morning in New York, the real thing, upstairs in the second-floor players' lounge of Arthur Ashe Stadium.

Laver is not tall—about 5-foot-8—and his hair remains a gentle puff of red. He is 75 now, and he was wearing a blazer that covered that famous oversized left forearm, the one they once measured and proclaimed to be as thick as Rocky Marciano's.

The first thing we talked about, naturally, was…the San Diego Chargers. Not kidding. Laver lives in Carlsbad, Calif., and is a huge Chargers fan. Knows well the heart-achy roller coaster of Chargers football. Had season tickets for years. Used to have tailgate parties. "Almost better than the games," he said.

But on tennis, Laver was enthusiastic. This was not a legend eager to pooh-pooh the modern game. He liked where tennis was. Sure, the current baseline endurance contests don't resemble the tennis he once played—wooden racket, serve and volley, charge the net, close the point—but he marveled at the athleticism, the defense and retrieval, the champions (Novak Djokovic, Rafael Nadal, Andy Murray, Roger Federer) crowded in this generation. "I think tennis is in great shape," he said.

Of course it was different. How could it not be? So much had changed—technology especially, wood replaced by composite rackets and strings that allowed players to take huge, sweeping cuts and put enormous spin on the ball. But it wasn't just the tech. The current pro lifestyle was almost unrecognizable—coaches, trainers, nutritionists, entourages, private jets. In his day, Laver would cram into cars with his Australian colleagues like Ken Rosewall, Roy Emerson, Fred Stolle, John Newcombe. They'd try beat each other by daylight, then go to dinner and share advice.

"We didn't have coaches," Laver said. "Your coaches were players that you'd compete against. [If] Roy Emerson's forehand's not working—I'd say, 'Well, you're hitting it too early, or too late.' We'd go out and practice until he got it right again."

The camaraderie was great, even if the experience was not always first-class. Laver chuckled as he described how he'd travel from Australia to Europe to play in the Italian Open—a pit stop in Singapore at the Raffles Hotel, then onto Karachi, then maybe Cairo, then finally onto Rome. He'd get an allowance of $350 or $400 a week.

The money now was breathtaking. The men's champion on Monday will earn $2.6 million, same as Sunday night's women's champion, Serena Williams.

Saturday's first men's semifinal was between Djokovic and Stanislas Wawrinka of Switzerland, and it went a full five sets, Wawrinka nearly pulling off an upset before the No. 1 seed Djokovic finally prevailed.

"Quite the ding-dong battle," Laver called it.

"He's tenacious," he said of Djokovic. "Very good groundstrokes, mixes the game up. He's got that forehand he can hit flat, or roll over it, and he can do the same on the backhand side—slice it sharply across court, or put the double-hander into play. But mostly it's that he hits the ball so deep. You can't attack it."

The second semi was far less entertaining. Nadal, unbeaten on hard courts all season, rolled easily over eighth seed Richard Gasquet. "He just seems to set the point up," Laver said of Nadal. "Plays it and plays it until he can run around that backhand, and hit that forehand away."

It had been a weird Open—a lot of one-sided matches, an early departure for Federer—but Monday's final would deliver the drama of No. 1 vs. No. 2, a battle of heavyweights. Laver was well versed in the Djokovic vs. Nadal rivalry—he'd been there in Melbourne, in the arena that bears his name, when the two men played a nearly six-hour marathon in the 2012 Australian Open final that Djokovic won.

"I think Nadal is playing more confidently, and Djokovic may be down a notch," Laver said. But these were small margins, almost unrecognizable, like going from an A-plus to an A. "There are levels at this level," he said.

Laver had a memoir arriving in the fall; Federer was quoted on the cover, calling Laver the "greatest champion our sport has known." But first there was this U.S. Open final. Laver planned to be there at Ashe—he'd been asked to do the coin flip at the start.

Djokovic. Nadal. No. 1 vs. No. 2. Maybe it would be another ding-dong battle.

Like everyone in tennis, Rod Laver couldn't wait. I definitely couldn't wait. But first I had to call my dad.

Write to Jason Gay at Jason.Gay@wsj.com