Nadal forced to retire as del Potro advances

“Ole’’ — the Spanish Warrior quit. Nine years later, Argentina’s Juan Martin del Potro is back in the U.S. Open final, unleashing the sport’s best forehand on defending champion and top-seeded Rafael Nadal of Spain, who couldn’t take it anymore.

His right knee acting up, Nadal elected to retire while losing in second set and trailing 7-6, 6-2 in the semifinals at Ashe Stadium.

Nadal — who is 32 and has weathered myriad injuries — was attended to by a trainer, who massaged, examined and taped his right knee early in the second set.

The injury timeout was an alarming scene to happen so early. Nadal also had his knee taped during his five-set victory over Dominic Thiem, but said the “issue’’ began in the Open’s second-round match.

It’s the just third time in 283 Grand-Slam matches Nadal has retired, according to the ATP.

“I felt something on the knee at 2-2 in the first set,’’ Nadal said. “I said to my box immediately that I felt something on the knee. I was just trying to see if in some moment the thing can improve during the match. But no, was not the day.”

Replays showed Nadal hopping in pain after rumbling for a forehand at 2-2, 15-0.

“You can imagine [it’s] very difficult for me to say goodbye before the match was finished,’’ Nadal said. “It was so difficult to keep playing at the same time that way — having too much pain. I hate to retire. That was not a tennis match at the end, no? It was just one player playing, the other one staying on the other side of the court.’’

Nadal said he didn’t think it was structural damage beyond recurring tendinitis. He still is dominant on the soft red clay of the French Open, but wouldn’t entertain a question of whether his knees are vulnerable on Flushing’s hardcourts.

“I know what I have,’’ said Nadal, who has 17 Grand Slam titles, three behind Roger Federer. “Similar thing than always.’’

In Sunday’s final, del Potro will face Novak Djokovic, who straight-setted Kei Nishikori 6-3, 6-4, 6-2 in the other semifinal.

Across the two sets, the Ashe Stadium crowd was filled with chants of “Ole, Ole Ole, Delpo!’’ Nadal normally is the fan favorite across the globe, but del Potro’s journey is a compelling one.

“I felt the energy from almost all the crowd were behind me because Rafa was the favorite to win the match,’’ del Potro said.

Nadal quitting took some shine away from del Potro. After losing the second set, Nadal took off his headband, put his racket in the bag and talked to the trainer. One of the sport’s true warriors, Nadal told him he was done. Nadal had skipped the last Open tune-up in Cincinnati to rest after winning the Rogers Cup in Toronto.

Down a break in the second set, Nadal jabbered at the umpire to protest a call he claimed came before the ball landed. During the argument, Nadal mentioned he was “going to retire anyway.’’ And so he did.

“I’m sad for him, but I’m also happy, too,’’ said del Potro, who added he looked to “put him running a lot.’’

“I saw him suffering a lot during the second set,” he said. “I say to myself, stay focused on my game, don’t look at him because you never know what could happen in that situation.”

For del Potro, it has been a long climb back since his win in the 2009 Open. He sustained a series of wrist problems soon after copping the title and, at age 20, dethroning Federer. It wasn’t until February 2016, his ranking at No. 1,041, that he made a return that would be lasting, though this is his first Grand Slam final since.

Del Potro had lost three straight Grand Slam matches to Nadal, including an epic five-setter in July at Wimbledon. But Friday was different from the start and he grew increasingly in control. Del Potro was flawless in the second set — 16 winners with just three unforced errors.

In the first set, del Potro was always pushing the action, getting Nadal on the move with his cranking groundstrokes.

Though del Potro blew two sets points at 5-4, the 6-foot-6 Argentine dominated the tiebreaker. Del Potro smashed away Nadal’s short return of serve for 5-2. Nadal butchered a forehand wide to fall behind 5-3 and triple set point. Nadal pounded a backhand in the net giving del Potro the set.

Asked about del Potro’s return to a Grand Slam final, Nadal said, “I can’t say that I am happy because I am not. I will not lie to you. But yes, he’s a player who went through a lot of issues.”