Ask future tennis pros who they would like to play if they could go back in time and Roger Federer just might be at the top of the list.
But who would the 20-time grand slam winner himself like to face at their peak if he had the chance?
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His preferred venue -- Wimbledon -- would hardly surprise anyone, since no man has won more than Federer's eight crowns.
As for the opponent, the 37-year-old didn't choose four players he has regularly called his idols, Boris Becker, Stefan Edberg, Pete Sampras or Rod Laver -- who tallied a combined 16 Wimbledon titles. Instead he opted for Bjorn Borg.
The Swede was renowned for hitting with spin -- atypical at the time -- high fitness levels, long locks of hair accompanied by a bandana and an ice-cool demeanor.
Borg knows what it is like to triumph at Wimbledon, too, having won five straight times from 1976-80 before chief rival John McEnroe ended the Swede's 41-match unblemished streak at the All England Club in the 1981 final.
Changing surfaces was no issue for Borg, either, as he collected six French Open titles, a haul bettered only by the "King of Clay," Rafael Nadal.
But Borg stunned the tennis world by retiring aged 26 in 1983 when he lost motivation and didn't win another match in a smattering of comeback outings over the next decade.
Borg and Federer have got to know each other more in the past two seasons through the Laver Cup, the successful team exhibition created in part by the Swiss' management company, Team8.
'A class act'
So why indeed Borg over anyone else?
"Just because I think he's done so much for tennis," Federer told CNN Sport in an interview last month in his training base of Dubai. "He's one of the true legends of our sport, a class act. A good friend of mine, too, and I would've loved to play against a guy like that. Super sweet as well."
Federer -- now in Melbourne as he prepares to defend his Australian Open title -- said that when he dethroned five-time defending champion Sampras at Wimbledon in 2001, Borg "sort of thanked me for protecting his five-year reign."
"And then who knew that years later, I would tie him and lose, like him, in an epic sixth final," added Federer, referring to the 2008 finale when he fell to Nadal in five sets in what many consider the greatest match ever.
"So for me I guess it would have to be at Wimbledon. At the French Open I think it would be too one-sided, his way."
The headbands, of course, would be in place.
"His is terry cotton, so he's got a different type of bandana," noted Federer.
Regarded as somewhat of a tennis traditionalist, best-of-three sets wasn't an option for Federer. And he wanted the noise levels kept to a minimum.
From both of them, that is.
Five sets, not three
"He's got a bit longer hair than I have at this point, and I'm maybe walking in with a blazer trying to go back in time even more so," said Federer. "Yes, and I think there would be no grunting going on, there would be just hopefully really good tennis.
"Has to be five sets, just because it's just so much more epic when it's five sets, and you would talk about it for years to come. And it's very personal, I must say also with any player that you've played five sets against, you will always remember that very match.
"Whenever you see each other maybe down the road in 20 years, you can always say, 'Remember that match?' Best of three sets sometimes just evaporate and they go, but best of five, they stay with you forever."
Federer said he would win in this dream scenario, striking a forehand down the line on match point.
Borg as captain
What would he say to Borg at the net exchange?
"You'll get the next one," Federer said. "And he's probably anyway beaten me so many times before, so he gave me that one."
Rather than dueling, Borg captains Federer on Team Europe in the Laver Cup.
Federer, Novak Djokovic -- back to being the man to beat in tennis -- and eventual ATP Finals winner Alexander Zverev were all teammates as Team Europe downed Team World in Chicago in September.
Nadal featured in the inaugural edition in Prague in 2017 and is set to return in Geneva this year.
Stories he can tell
Borg's presence is invaluable, said Federer.
"It's surreal, the stories he can tell, and people were laughing that he doesn't say much on the bench," he said. "But I understand, I think, of all people he knows what it is to be at the top and what it is to stay calm, stay focused and in the moment.
"So I think the Laver Cup has really produced that for a lot of guys like Zverev, and Rafa, and Novak, to get a glimpse into Bjorn's head, how he would think as a winner and how laid back he is away from the tennis."
Roger chooses LeBron, too
On the subject of hypotheticals, Federer was asked what skill from another athlete he would incorporate into his game.
He cited a world famous four-time NBA most valuable player and 14-time all-star.
"Size and strength, maybe, of LeBron James, something like that," said Federer. "Sometimes I wonder, 'Am I getting too small?' because everybody is taller than me slowly on the tour.
"Back in the day, my size was normal. Nowadays everybody is getting taller and bigger and stronger."
Listed as 6 feet 1 inch tall, it makes Federer tied for the second shortest player in the top 10 along with Nadal and Dominic Them. Japan's Kei Nishikori registers at 5 feet 10 inches.
In the first week of the rankings in 2005, only three players in the top 10 were taller than Federer.
Not that Federer has been hindered by size during his consistently record-breaking career.