NEW YORK — Juan Martin del Potro's first match inside Arthur Ashe Stadium produced his second trip to a Grand Slam semifinal.

The sixth-seeded del Potro overcame a sluggish first set Thursday and figured out the blustery wind inside the cavernous stadium to defeat No. 16 Marin Cilic, 4-6, 6-3, 6-2, 6-1 in the U.S. Open quarterfinals.

"It's so beautiful playing in front of this crowd," del Potro said. "I'm so happy it happened this way."

Jettisoned to smaller courts for every match over his two years at Flushing Meadows — despite his ranking — the Argentine finally got to play on the big stage.

He had a rough time handling Cilic's serve in the first set, and was down a break early in the second. That's when he figured things out and rolled off 17 of the last 20 games.

"He was not missing," Cilic said.

Del Potro is in his second major semifinal, adding this to his trip at the French Open earlier this year, where he blew a lead and lost in five sets to Roger Federer. Del Potro's next opponent will be No. 3 Rafael Nadal or No. 11 Fernando Gonzalez, whose quarterfinal was interrupted by rain with Nadal leading 7-6 (4), 2-2.

After winning the first set, Nadal sought treatment from a trainer. The exact nature of Nadal's problem wasn't immediately clear, but he did have stomach muscle issues earlier in the tournament.

In earlier action on the main court, Venus and Serena Williams advanced to their 10th Grand Slam final with a 7-6 (4), 3-6, 6-2 victory over Russia's Alisa Kleybanova and Ekaterina Makarova.

The Williams sisters are 9-0 in their previous final appearances, though this is their first trip to the U.S. Open final since 1999.

"Hopefully, that's a record that won't end yet," Serena said. "We really want this. I'm sure whoever we play really wants it, too."

Todd Parrott and Carly Gullickson won the first trophy to be handed out this week at Flushing Meadows, in mixed doubles, upsetting defending champions Cara Black and Leander Paes, 6-2, 6-4.

Del Potro got a matchup with Cilic thanks to the Croatian's three-set upset over No. 2 Andy Murray on Tuesday. In del Potro, Cilic saw a near mirror image of himself — 6-foot-6, big serve and they were even born five days apart in September 1988.

But Cilic's sharpness from the Murray match vanished in this one. He committed 53 unforced errors against 29 winners, while del Potro was on his game — 24 unforced errors and 27 winners.

"Andy, he doesn't have as much power as Del Potro has," Cilic said. "And it was a little bit hotter that day and the ball was going through the court more and jumping much more."

This match was played with temperatures in the mid-60s and winds that gusted at around 20 mph at times. It took some of the power out of a match that should have featured a lot.

"I cannot start the match like today," Del Potro said. "I was thinking about other things, and the weather was bad. But it was bad for both players. I just need to be in focus in the beginning of the match until the last point and play my game."