Rafael Nadal and Roger Federer will meet in Sunday's final of the Shanghai Masters, just the latest chapter in their storied rivalry.
The celebrated duo have faced one another 37 times, with the Spaniard and world number one Nadal winning 23 of their contests.
And the 31-year-old Nadal, who has never won the Shanghai Masters, will be slight favourite this time because he goes into the showdown on a terrific run of form and Federer faces a quicker turn around.
Nadal, a 16-time Grand Slam champion, triumphed at the US Open and then last week at the China Open for his sixth title of another remarkable campaign.
But he was forced to survive a rollercoaster with fourth seed Marin Cilic in their semi-final, saving three set points in the opener before pulling through 7-5, 7-6 (7/3).
The Swiss Federer, the world number two chasing a second Shanghai crown, rolled back the years to recover from a set down and defeat Juan Martin del Potro 3-6, 6-3, 6-3.
The 36-year-old Federer afterwards dismissed concerns about his shorter rest time -- his was the later match -- and called the rivalry with Nadal "special".
"The way we both play, play so very different from one another, and also the attitude, the way we go through our lives, it's all very different in some ways," said Federer, a crowd favourite in Shanghai.
"But we have a similar mindset in the big moments, I came to realise that when we played doubles (together recently at the Laver Cup).
"No sense of urgency or panic. You can tell we have been there many, many times before.
"He's a great champ and he's definitely one of the guys that makes me a better player.
"He made me rework my game and go back to the practice courts and think about what I could change.
"For that I'm happy for the losses I took (against him) and it's nice that at this stage of my career we still have these matches going on."
Federer had said that he wanted revenge over the 16th-seeded Argentine Del Potro for defeat in the quarter-finals at the US Open this summer.
And he eventually got it.
Del Potro, the 2009 US Open champion whose career has been blighted by wrist injuries, quickly allayed fears that his latest problem would be a major handicap.
The 29-year-old fell and hurt his left wrist in winning his quarter-final and there were suggestions he may not even make Saturday's match.
But he showed no ill effects in stunning the pro-Federer crowd to break for 4-2 in the first set.
And Del Potro grasped set point following a thrilling rally that had the spectators whooping, only for 19-time Grand Slam champion Federer to inexplicably shank his volley out of the court.
The second set went with serve until Federer, going after a 94th singles title, made the breakthrough on the Del Potro serve to inch ahead.
Del Potro began showing irritation, engaging in a series of discussions with the umpire, complaining about the crowd chatting during points.
Federer sent the match into a deciding third set and he got the break early to tee up another Nadal meeting.
- 'Tough match' -
Croatia's Cilic had only ever got the better of Nadal once in five previous meetings, but he made the top seed work hard for this latest win.
Nadal said he was just glad to be in the final.
"The way doesn't matter," he said with a smile.
"We are at the highest level of our sport so nobody wins easy.
"And if you want to compete in the most important events of the year and try to go for the victories, for sure you're going to have tough matches, and today was one of them."
Nadal displayed a flash of irritation at one point during the second set, as he and Cilic swapped breaks, bashing himself on the knee twice in annoyance with his racquet.
The Spaniard, who has surged back to world number one after a succession of injuries, brushed the incident off.
"Sometimes I get frustrated too, that's all," he said.