BEIJING-Rafael Nadal was forced into a third set before the world number one piled the pressure on Grigor Dimitrov to reach the final of the China Open on Saturday.

The 31-year-old Spaniard, enjoying a late-career flourish and chasing a sixth title this season, beat off the Bulgarian third seed 6-3, 4-6, 6-1 in their semi-final on Beijing's outside hard courts.

Nadal, good friends with Dimitrov, will face temperamental Australian Nick Kyrgios in Sunday's final. Kyrgios, pulled off a stunning 6-3, 7-5 win over starlet Zverev.

Dimitrov battled back from a set down to take it to a deciding third set. But with the crowd behind him and Dimitrov visibly tiring, the 16-time Grand Slam champion Nadal stepped up a gear to ram home his superiority.

Nadal is chasing a sixth title this season but to do so he must beat the enigmatic Kyrgios, who is becoming a crowd favourite in Beijing.

A year ago the 22-year-old was suspended by tennis authorities for his behaviour in a defeat in Shanghai during which he appeared to give up and argued with the crowd.

Kyrgios says he wants to show how far he has come and the 19th-ranked Australian did just that as he bustled past Zverev, the world number four from Germany, in an entertaining and high-quality semi-final.

Kyrgios's exuberance won favour with the crowd in the Chinese capital and after winning one thrilling rally he turned to the spectators and gestured with flailing arms for them to keep roaring him on.

In contrast, Zverev smashed his racquet on the floor, earning a warning from the umpire, when Kyrgios grabbed the decisive break in the second set.

Nadal responded to a simmering debate about the amount of tennis the top stars play, saying: "We are not 20 years old anymore."

Despite his advancing years Nadal is enjoying a stellar season following a catalogue of injuries in previous seasons, winning five titles including the US Open and French Open.

But many of his rivals are suffering injury or fatigue as the season approaches its climax, with Novak Djokovic, Stan Wawrinka, China Open defending champion Andy Murray and Japanese star Kei Nishikori all missing.

However, the oldest of the lot, Roger Federer, is set to compete in Shanghai next week and Nadal refused to add his powerful voice to those demanding fewer tournaments.

"When I have been in that position (injured), I don't remember the people talking that much about these things," Nadal said after defeating the 26-year-old Dimitrov in their semi-final. "The problem now is there is a couple of players (injured), it's a coincidence, first thing. Second thing, we cannot forget that we are not 20 years old anymore.

"It is true that the calendar is tough, but at the same time it is true that Federer has 36 years, I think, I have 31, Novak 30, Andy 30, Nishikori, I don't know, 27. It is normal that at some point these kind of players that are playing a lot of matches and a lot of years in a row, at some point they have some problems."