Here's hoping for Federer-Nadal IV

Rafael Nadal has yet to play a tennis match as a 23-year-old. And yet, after the remarkable events in Paris, why does it feel as if his Grand Slam window has significantly shrunk?

Because Roger Federer, approaching the venerable age of 28, has reasserted himself in the mano-a-mano race for major titles.

"It almost gets forgotten a little bit," said Federer two weeks ago after he won his first title at Roland Garros. "I don't want to say it means the most to me, but it's an incredible feeling already having reached 14 and not having been sort of derailed by maybe losing a couple of Grand Slam finals against Rafa."

Going back to the 2006 French Open, they have met in Grand Slam finals seven times. After they split in 2006 and 2007, with Rafa taking Roland Garros and Federer continuing to own Wimbledon, the chemistry changed. Nadal won his fourth straight French Open, then beat Federer in a brilliant final at the All England Club and, to open the 2009 season, prevailed in another five-set final at the Australian Open.

Nadal had never won a major title outside of Paris, but suddenly, nothing was guaranteed for Federer, who has now lost five of seven major finals to the Spaniard.

This year's French Open tilted the axis back in the favor of Federer. Even though it was Robin Soderling who took out Rafa in the fourth round, with surprising ease, Federer was the last one standing in Paris. When he beat Soderling in an anticlimactic straight-sets final, he had finally usurped some of Nadal's burnt-red turf.

Federer now finds himself a fortnight from breaking Pete Sampras' record of 14 major singles titles.

All of which makes Wimbledon, which begins Monday, a fascinating case study in the Nadal-Federer dynamic. For the fourth straight year, they will be the top two seeds at the All England Club. To help quench the insatiable hunger for the anticipated Rafa-Roger IV, we bring you five more things to know about this fierce, feverish rivalry:

1. This most appetizing final would make history:

Nadal and Federer, based on their seeds, are expected to reach their fourth straight Wimbledon final. Considering a finalist must hack his way through a 128-man field and win six consecutive matches, this would be remarkable.

The last time two men met in three consecutive finals before Rafa and Fed was 1988-90 when Stefan Edberg and Boris Becker did it; in 1990, Edberg took the rubber match in a five-set thriller.

Going back to 1877, when the first final was contested, only one duo has gone at it in four straight finals: Wilfred Baddeley and Joshua Pim. Of course, they benefited from the rule (rescinded in 1922) that granted defending champions a bye straight into the final.

2. They enter the tournament [insert George Hamilton reference here]:

After bailing on their respective grass warm-up events in London and Halle, Germany, Nadal and Federer are tanned and, presumably, relaxed.

A battery of tests confirmed that Nadal's aching knees are troubled by chronic tendinitis, and he spent the past two weeks at home in Manacor, Mallorca, Spain, working out with part-time coach Francis Roig.

Thus the quickest transition in Grand Slam tennis -- from clay to grass -- will be achieved by Nadal and Federer without the benefit of match play. Instead, they will hone their grass games in the anonymity of the Aorangi Park practice facility, tucked behind Henman Hill.

"I am going to give my 200 percent to be ready for the most important tournament in the world," Nadal said last week. "I will not go out and play, especially on the Wimbledon Centre Court, if I am not 100 percent ready to play."

It's a good thing Nadal is a tennis player, not a mathematician.

3. In the past five-plus years, only three men have broken the Federer-Nadal monopoly in Grand Slam events.

So, knowledgeable tennis fans, who are they? To guess, do not immediately read below.

Going back to 2004, Federer and Nadal have won 19 of the 22 majors contested. Including Federer's first Slam, 2003 Wimbledon, the two have combined to win six straight titles at the All England Club, five straight French Opens and five straight U.S. Opens. The weak link? They're only 4-for-6 at the Australian Open.

Congratulate yourself if you were able to come up with Gaston Gaudio (2004 French Open), Marat Safin (2005 Australian Open) and Novak Djokovic (2008 Australian Open). You may now treat yourself to staying home Monday and watching the first day at Wimbledon on ESPN2 and ESPN360.com.

4. Marriage apparently agrees with Federer:

Federer is undefeated in Grand Slam play as a married man, now 7-0. He's 12-0 overall, including his run to the title in Madrid, where he beat Nadal in the final.

It might be a coincidence, but … Federer won his 14th major title with pregnant Miroslava "Mirka" Vavrinec in the stands. Sampras won his 14th watched in New York by his pregnant wife, Bridgette Wilson.

Maybe it's time for Rafa to marry his 23-year-old girlfriend, Maria Francisca Perello. Her nickname is Xisca, and she's a former schoolmate of Nadal's in Mallorca.

"I think with the change coming in my life with the wife and baby," Federer said, "it's going to be [a] very exciting next few years.

5. Federer can regain the No. 1 ranking:

If Federer wins Wimbledon, marking his sixth title in seven years, and Nadal fails to reach the semifinals, Federer would return to the top of tennis for the first time since August.

Greg Garber is a senior writer for ESPN.com.