From 1983 to 2003, the world's top two players never met each other in the Wimbledon men's final.
It's about to happen for the seventh time in eight years - with a couple of twists.
Thanks mainly to a couple of guys named Roger Federer and Rafael Nadal, No. 1 vs. No. 2 Grand Slam finals became something of a regular occurance in recent years, at the All England Club and elsewhere. On Sunday, No. 1 Nadal will be involved in yet another 1-2 Wimbledon championship matchup, only it'll be against No. 2 Novak Djokovic - and they'll switch spots in the ATP rankings a day later.
As of Monday, Djokovic will move up to No. 1, and Nadal will slide down to No. 2, regardless of Sunday's outcome. Whichever man wins, it will be the sixth major title in a row that's gone to Nadal (French Open, Wimbledon and U.S. Open in 2010, French Open in 2011) or Djokovic (2010 Australian Open).
"One guy played unbelievable the first half of the year, so he's the new No. 1," Nadal said. "We just can congratulate him, because what he did this first part of the season is something really impressive, really fantastic."
That's definitely the case.
Djokovic is 47-1 in 2011, including a 4-0 record against Nadal, beating him in two hard-court finals and two clay-court finals.
"The four times I won against him this year can probably help me in some ways mentally prior to this match," said Djokovic, who is 11-16 against Nadal overall, including 0-5 in Grand Slam tournaments.
The 24-year-old Serb won the first seven tournaments he entered this season, before his 43-match winning streak, dating to the Davis Cup final in December, ended with a loss to Federer in the French Open semifinals.
"He's the best player in the world (at) the moment," Jo-Wilfried Tsonga said after losing to Djokovic in Friday's semifinals.
That victory moved Djokovic into his first final at Wimbledon, and fifth at a Grand Slam tournament. He's 2-2 so far, winning the Australian Open twice, and losing in two U.S. Open finals: to Federer in 2007, and to Nadal last year.
This one carries the most significance to Djokovic, though.
"First time I watched tennis or anything related to tennis was Wimbledon ... when I was 4, 5. I remember those days," he said. "I remember always Wimbledon being 'the one.'"
Nadal, meanwhile, is seeking his third Wimbledon title and 11th Grand Slam trophy overall. A month past his 25th birthday, Nadal would be the second-youngest man to get to 11, barely behind Bjorn Borg.
And Nadal already would be tied for fourth-most Grand Slam titles in history, trailing only Federer (16), Pete Sampras (14) and Roy Emerson (12).
Nadal refuses to talk about pursuing Federer's record.
"I think about the number '10.' That's what I have at home. That's what I'm able to see when I go back home, in my bedroom," Nadal said. "I don't have 11, I don't have 12, I don't have 15, or 16; 16 is very far. I believe the number is not going stop there. Roger will have more chances to win more."
Others are more willing to assess Nadal's chances of surpassing Federer.
Sampras, for one, said this week he wouldn't be surprised to see Nadal do it.
Nadal has won 20 consecutive matches at Wimbledon and is 32-2 at the grass-court Grand Slam since the start of the 2006 tournament, reaching five finals in a row.
He lost to Federer in the 2006 and 2007 finals, and beat him for the 2008 title - those were three of their seven 1-vs.-2 major championship matches - then missed Wimbledon in 2009 because of tendinitis in his knees, before beating Tomas Berdych in last year's final.
John McEnroe was ranked No. 1 when he lost to No. 2 Jimmy Connors in the 1982 Wimbledon final. But there wasn't another 1-2 title match at the All England Club until 2004, when No. 1 Federer beat No. 2 Andy Roddick. They repeated that matchup a year later, and then Federer and Nadal began their string of finals.
Now Nadal and Djokovic meet in what might only wind up being the first top-two Grand Slam final between them.
No matter what Monday's rankings will say, McEnroe knows which of those he thinks is No. 1 for now: Nadal.
"The guy's one of the greats, no doubt about it," McEnroe said, "and you can make an argument for him being the greatest."