Roger Federer and Rafael Nadal will meet in the Indian Wells semi-final for the first time since 2017, having won their respective quarter-finals on Friday.
Switzerland's fourth Swiss, Federer (37), passed the Polish Hubert Hurkacz (6-4).
The second Spanish seed Nadal (32) had to be treated for a tough 7: 6 (7-2) 7-6 (7-2) over Russian Karen Khachanov on the right knee.
Nadal said he "hopefully" will be ready for Saturday's semi-final.
"I will do my best to recover – these are the games I want to play," said the 17-time Grand Slam champion.
"It's great to play against my biggest rival in the later stages of our career and continue to compete against each other."
The two greats played last in the final of the Shanghai Masters in October 2017, as Federer won in sets.
The 20-time Grand Slam champion has won each of his last five games, but Nadal leads in his direct encounter 23-15.
"I do not think these games are so important to be honest," said Federer, who has yet to make a set in this year's tournament.
"It has been a long time, unfortunately for the rivalry, for us or for myself, it is always better to continue to play against him.
"The fans may be more excited about us than me because I always have to focus on my own game.
"But it's always putting more energy into the stadium and for both of us."
"I had a hard time"
Federer is chasing a sixth record Indian Wells title – he's five with Novak Djokovic – while Nadal is looking for his fourth place finish.
In the second semi-final in California, the Austrian Seventh Dominic Thiem meets Canada's 13th seed Milos Raonic.
World Number Four Federer broke Hurkacz, 22, in the fifth game of the game before doing so again in the third game of the second set.
Nadal had a much more difficult duel against the twelfth seed Khachanov, who needed a medical break after the third game of the second set, in which the band was placed under his right knee.
Number two in the world looked uncomfortable but saved a set point so as not to be brought to a decision maker before impressing again in the tie-breaker to secure the victory in two hours and 16 minutes.
"I had a hard time against a very, very tough opponent," said Nadal.
"I came back and had chances, but he served great, then I had knee problems, but I could fight and find a way."