Del Potro, Djokovic set up US Open final showdown

Rafael Nadal retiring with an injury sent Argentine Juan Martin del Potro through, while Kei Nishikori was no match for Novak Djokovic in the other semifinal.

Novak Djokovic plays a forehand during his semifinal against Kei Nishikori.

World No. 1 and defending US Open champion Rafael Nadal retired injured from his semifinal match against No. 3 Juan Martin del Potro. He was trailing 7-6, 6-2 when a knee problem forced him to stop after almost two hours of playing time. 

“It was difficult for me to keep playing. I was in too much pain,” he said. Nadal, who was bidding to win his 18th Grand Slam title, faced similar issues during his third-round match against Russia’s Karen Khachanov. This is the second time he has retired in a Grand Slam this year.

del Potro will return to a Grand Slam final nine years after his first, when he defeated Roger Federer at the US Open in 2009. He will face Novak Djokovic, who beat Kei Nishikori in straight sets in the second semifinal.

Read: History at stake as Serena, Osaka meet in final

Sixth-seeded Djokovic reached his eighth US Open final, defeating Kei Nishikori 6-3, 6-4, 6-2.

Djokovic is bidding to win his third US Open title and 14th Grand Slam overall. He avenged his most recent last-four loss in New York – in 2014 vs. Nishikori, the only prior time they had met in Flushing Meadows.

“I came out of the blocks with great intensity and focus,” Djokovic said.

Djokovic missed last year’s tournament owing to an elbow injury. Should he win on Sunday, he will equal Sampras’ record of 14 Grand Slam titles. Only Roger Federer (20) and Rafael Nadal (17) will have more titles than him.